发帖到 HN 后，我的网站被 AI 机器人流量淹没

1. 我发帖到 HN，然后我的网站被 AI 机器人流量淹没了

过去几年，我一直在开发 sprinklz.io，这是一个可定制的订阅阅读器，其功能之一是可以降低新闻源中某些话题的优先级。

一个月前，我把它发到了 HN，获得了大约一百个赞，不错！看来人们真的厌倦了听到关于 LLM 的消息，他们喜欢能够从订阅源中降低这些内容的优先级。这很好地展示了为什么这样的工具有用。一切都在好转，然后……

我的网站变慢了。真的，非常慢，慢得让人痛苦。起初我把它归因于帖子突然走红带来的额外关注。像任何开发者一样，我既庆祝了一番，也发誓将来要让网站更有弹性。但奇怪的是，缓慢持续着，甚至在我的帖子发布几天后开始变得更糟，而我记录的指标也说不通。比如，你知道，有相当一部分真正活跃的登录用户，但服务器却表现出高得离谱的负载。

于是我查看了一些数据。我为每个端点添加了顶层日志记录（每个 URL 路径被请求了多少次），结果发现大多数请求甚至没有尝试获取新闻文章！作为参考，我的网站是作为单页应用构建的，这意味着大多数请求甚至没有运行渲染页面所需的 JavaScript（！）。

进一步挖掘，我查看了聚合的 NGINX 日志来找出滥用者，你绝对不会相信，但事实证明我们近一半的流量来自一个特定用户。我不会点名，但我查了一下，他们自称是一项服务，监听网站的变化，然后将其总结成 AI 垃圾新闻通讯。而所谓‘监听变化’，我的意思是每分钟多次查询我们的网站。已屏蔽。

其他几个是你熟知的标准爬虫，并且很友好地表明了自己的身份。Claude bot、OpenAI bot、谷歌的搜索索引器，还有其他几个。我甚至在路上还遇到了一些漏洞扫描器。至少，有人在试图访问 -/wp-content/phpinfo.php（我的网站不是 WordPress 站点）。我添加了 robots.txt 来阻止大多数 AI 扫描器，但允许 google-bot 和其他与搜索相关的流量，并让 claude 查询所有漏洞路径并模仿扫描器，以确保我没有泄露任何东西。我还添加了合理的速率限制，等等，等等。

不过最重要的教训是，是时候让我的网站变得更快了。我希望我的网站有一天能够处理 xxx QPS 的真实流量，而且它应该比过去扩展得更好，即使在重负载下也是如此。受这次经历的启发，过去几周我对底层基础设施做了不少改进，这些改进应该会为所有用户带来相当可观的性能提升。

附注：如果你想看看，这个网站完全免费，可在此处访问

简而言之，它让你定义自己的自定义项，此外还有像 Hacker News 的积分总数之类的东西。你可以用它来过滤主题，比如 AI 或 LLM，但主题完全是任意的，你可以编写自己的自定义项。

2. 用 LLM 让 Emacs 网页浏览器再次伟大

当我向人们介绍 Emacs 网页浏览器时，他们的第一反应是“等等，Emacs 有网页浏览器？！”，接着是“好吧……我想那也算是个网页浏览器”。

Emacs 网页浏览器旨在基于终端、纯文本的环境中渲染网页，嗯，它的表现完全如你所料。它在只有 HTML、内容较少的网站上运行良好，但对其他任何东西就不太行了。

问题在于，Emacs 主要是一个纯文本编辑器，而现代互联网在很大程度上并非基于纯文本。简单的 HTML，以 1990 年代的简单风格设计，可以清晰地转换为纯文本，但现代 UI 设计，带着它的视觉样式、大量 JavaScript，以及整体上的混乱，就不太行了。

Emacs 网页浏览器本会很棒，只要我们能找到办法回到过去……

好，那么计划很简单。我们拿现代网页，把它们的源代码重写成老派的简单样式 HTML，然后把它输送给 Emacs 网页浏览器。我们只需要找到一种简单且大规模地做到这一点的方法。

所以，嗯，你没忘记 LLM 吧？能以有望减少世界上垃圾内容数量的方式使用它们，真是件好事。

基本上，计划就是我们写一个程序，它：

在 firefox 中打开一个网页
加载页面并运行所有 JavaScript
让 LLM 生成一个可复用的程序，将当前页面的内容转换为简化文本
将生成的 JavaScript 注入 firefox 浏览器
抓取新的页面源代码并转发给 Emacs 网页浏览器。

是的，所以，我一直在用它，而且运行得非常好。实际上，我可以在许多以前 eww（emacs web wowser）无法运行的网页上使用它。

以下是一些前后对比示例：

Clojure 的 mapcat 文档

图 1：（之前）使用 eww-readable

图 2：（之后）使用 simpleweb-simplify-page

生成初始修饰程序需要一点时间，但一旦生成，它运行得相当快，在日常浏览中，它大多不需要额外的 LLM 调用。我自己一直在使用它，并且很享受这种体验。

源代码在这里：https://github.com/sstraust/simpleweb

并且是开源的，可以免费安装，等等等等。

2. 如果技术变得更好了，为什么一切都变得更糟了？

我想我们都知道答案：糟糕的激励。

技术让系统更有效率，但它实际上并不会让你个人更有效率。让计算机更高效的工具，也让人更高效地利用你的时间、注意力和福祉。我说的是神经网络，宝贝。

我第一次注意到这个问题是在 2018 年。或者更确切地说，我注意到我有一个问题，那就是每天花 3 个小时看星际争霸 2 的录像，然后想知道时间都去哪儿了，以及我怎么又熬到凌晨 2 点。

对我来说有趣的是，直到 2010 年代后期我才有这些问题。我至少从 2000 年代中期就有了联网的电脑，不久之后就有了装有 twitter 和 reddit 之类应用的智能手机。可能是我这些年来变得不那么有韧性了，但我有一种隐隐的怀疑，是电脑变了。

我无法确切地指出原因，但我有一种感觉，每次我与某个系统或网站互动时，我都在玩一种对抗性的游戏，我试图只是过我的日子，也许读一篇关于电脑的小文章，而它们试图找出一种方法让我在它们的网站上多待一会儿。

我还有一种感觉，随着软件工程从爱好者和热衷者的学科转变为越来越多通过金融或商业思维轨道成长起来的领导者，我们发现我们曾经热爱的这些主要工具变得既极其平淡又极其有利可图。

那么我们能做些什么来让它停止呢？

去接触草地。真的，当世界是这样的时候，我认为最好的解决办法就是离开。这并不容易，尤其是当计划往往是在网上进行的时候，但如果你能安排好的话，我保证在公园里和朋友下棋的一天比你在互联网上能花的任何时间都要好。
走上街头。我认为抗议是有效的，应该有更多人这样做。如果你愿意采取行动，这向他人表明他们也可以采取行动。
不要再回到同样的机器前。我想我们都有这种赌徒谬误，如果第一次没有回报，但有时会有回报，我们就会再试一次那台机器，但事情并不是那样运作的。如果你在亏钱，教训就是停止往机器里投币。

编者注：我一直在开发一个免费的可定制新闻阅读器，以此来消除我对现代互联网的一些不满。如果你不用这个，我建议关注个人博客和网站，因为完全离开这些大平台要好得多。

编者注 2：我还没有把这篇文章发布到我的 rss xml 中，因为我还没准备好为它发送通知。将在未来几周内添加。

3. Deft 版本 0.2.0

现在 deft 0.2.0 已经发布，我想是时候谈谈我构建了什么，以及为什么构建它。

Clojure 的“一切皆 map”工具包的要点在于，getter 和 setter 是浪费时间。Clojure 的构建在很大程度上是为了回应 2008 年糟糕的 Java 工作流程，当时你必须编写 getter、setter 和 builder，并承担所有这些没人喜欢的臃肿代码。

问题在于，如果你想使用内置的 defprotocol 和 defrecord 来表示数据，并且想定义依赖于某个字段存在的函数，那么将这些信息编码到协议中的唯一方法就是向其中添加 getter 和 setter 方法。真恶心。

你也可以使用协议 + malli schema 的组合来表示这一点，但当你使用它时，你需要指定“这个函数接受一个既实现此协议又实现此 Malli schema 的输入”。同样恶心。

我们想要的是可以以 defprotocol 和 defrecord 风格使用的东西，但默认情况下为我们提供所有 getter、setter 和类似 map 的东西。关键洞察是，如果记录中存在某个字段，我们就能获得所有其他好东西，所以我们只需要添加对带有必需键的协议的支持。

Deft v0.2.0 添加了对类型和协议定义中命名空间键的支持。也就是说，你现在可以这样做：

(defp Positioned :required-keys [::pos - ::Point])

以及

(deft Circle [::location/position radius])

(>Circle ::location/position [1 2] :radius 12)

这很有用，因为你现在可以定义依赖于这些字段存在的方法，例如：

(defp Gremlin :extends [location/Positioned])

(defmethod game-object/get-hitbox ::Gremlin [self]
  (js/Matter.Bodies.rectangle
   (get-in self [::location/pos ::location/x])
   (get-in self [::location/pos ::location/y])
   15 15))

来看看吧！

https://github.com/sstraust/deft

4. 多少 LLM 才算太多 LLM？

我上周读完了《On the Edge》，它很糟糕。并不是说我不尊重 Nate Silver。我非常尊重他。所以当他的关于赌博和冒险的奠基性著作变成一篇杂乱无章的散漫之作时，我感到惊讶和失望。尽管如此，作为一个内心有强迫症的人，我还是硬着头皮读到了最后，在那里我看到了这条消息：

“ChatGPT 在写这本书时提供了重要帮助，在构思章节副标题、隐喻和类比等内容时充当了创作灵感，并帮助我完善了对那些很可能在其语料库中得到充分体现的技术主题的理解。”

严格来说他是手写这本书的，严格来说他是把字母打到键盘上的，但你知道，他真的如此吗？他真的把全部的思想、心智和存在都投入到页面上的每一个字了吗？也许吧。我想起了绝对的经典 [Simple Made Easy](https://www.youtube.com/watch?v=SxdOUGdseq4)，在这个视频中，核心讲座的很大一部分都建立在定义精确的语言、并准确表达你的意思之上。当你把这项工作外包出去时，你不仅跳过了措辞选择，还跳过了那种思考，并且错过了那种组织性和思维清晰度。

在阅读 Nate 的书时，有些语言感觉像是深深融入了 Nate 思维的组织结构之中，而有些部分则像是事后添加的，两者之间存在真实而明显的差异。尤其是后面的章节，感觉缺乏那种将一切统一在一个愿景之下的思维压缩。我很难过，因为这本来可以是一部非凡的作品，而且很明显，人们付出了大量努力，尤其是在采访和数据收集方面，感觉它只是缺少了最后那一块缺失的洞察，无法将其彻底完成。

那么，多少大语言模型才算太多？嗯，说到人际连接，我会说答案几乎是零。我不想读你AI生成的电子邮件，当然也不想读你AI生成的文章。我更愿意读你的提示词，因为我在意的是你，没错，你个人是怎么想的，我想理解你想要传达什么。

别误会，我在合适的用途上很喜欢大语言模型。我很乐意用大语言模型处理医生笔记，来构建预测流感是否在传播的模型。但说到写作，尤其是这种写作，就感觉太没必要了，因为当你写下自己的想法时，我已经得到了我想要的，中间再加一道反而显得很傻。

作为一名扑克玩家和博弈论学者，我相信Nate会欣赏这句话：“如果你都懒得写，那我也懒得读。”而且，尽管我相信艺术可以独立于艺术家存在，但内心深处，这个说法对我来说是成立的。并不是说同一个人写出的同样文字与来自大语言模型的同样文字有本质不同，但它确实让我那小小的贝叶斯估计器有点失准。

如果我认识的最聪明的人花了10,000小时写作、编辑、打磨并出版了一本500页的小说，这告诉我的不只是我认识的最聪明的人对某个话题有一些想法，还告诉我他们决定花他们宝贵时间中的10,000小时，以及他们宝贵的精力，把这个想法传达给我。我读它花的时间与你写它花的时间成比例（而且通常少于），这让人感觉很好，因为这向我表明你在意创造这次交流所花的时间和精力。

而且，并不只是完全由AI生成的垃圾内容会撞上这道门槛。当你把大语言模型融入你的写作，哪怕只是一点点，你也会失去处理自己想法和建立人际连接的能力。

5. 用大约350行Clojure构建国际象棋

我最近发布了deft，一个使用普通map来定义类型和协议的Clojure库，于是，为了试用一下，我用Clojure写了国际象棋游戏。

国际象棋对任何类和接口系统来说都是一次很好的试运行，因为它相当小且自包含（而且类的选择也相当明显），但它也带有真实应用的一些混乱之处，因为你想写得简洁，但仍然必须处理边缘情况，比如王车易位和吃过路兵。

所有棋子都是我手绘的，并用这个小reagent片段来渲染显示，

[:h-box
 (doall (for [x (range (count tiles))]
                  ^{:key x}
                  [:v-box
                   (doall (for [y (reverse (range (count (nth tiles x))))]
                     ^{:key y}
                     [:p {:style {:background-color (cond
                                                      (= [x y] @currently-selected-location)  "yellow"
                                                      (= (mod (+ x y) 2) 1) "white"
                                                      :else "black")
                                  :height "4rem"
                                  :width "4rem"
                                  }
                           :on-click (fn [] (move-selected-piece
                                                    game-board-atom
                                                    currently-selected-location
                                                    [x y]))}

                      (if (not (nil? (get-in tiles [x y])))
                        [:img {:src (image-path (::piece-type (get-in tiles [x y])))
                               :style {:height "100%"
                                       :width "100%"
                                       :filter (when (= (::color (get-in tiles [x y])) ::black)
                                                 "invert()")}}]
                        "")]))]))]

但比较有意思的一点是如何表示棋盘状态及其所有棋子。

我做了某种显而易见的事，定义了表示棋子的类型，然后把棋盘定义为棋子的8x8网格

(deft ChessPiece [color piece-type])


(deft ChessBoard [tiles - [:vector [:vector [:or :nil ChessPiece]]]
                  curr-move - [:enum ::white ::black]
                  move-history - [:vector ChessMove]])

然后对于棋子行为，我制定了协议，定义棋子如何显示以及如何移动。

(defp PieceType
  (image-path [this]))

(defp MovablePiece
  (is-valid-move-for-piece? [this game-board start-location end-location]))

下面是骑士的一个例子：

(deft Knight []
  PieceType
  (image-path [this] (image-asset "knight_white.png"))
  MovablePiece
  (is-valid-move-for-piece?
   [this game-board start-location end-location]
   (and
    (let [direction (map abs (map - end-location start-location))]
      (or (and (= (first direction) 1) (= (second direction) 2))
          (and (= (first direction) 2) (= (second direction) 1))))
    (is-valid-end-location? game-board start-location end-location))))

is-valid-move-for-piece? 返回一个真值或假值，表示“我的棋子能否移动到这一格”。

这对大多数棋子都很有效，但对于更复杂的移动来说还不够，比如王车易位，其中多个棋子同时移动。为了处理这种情况，我们使用另一个多方法

(defmulti special-move-for-piece (fn [x & args] (:type x)))

它只为特殊移动定义，并返回修改后游戏棋盘的實際状态。

所以对于兵来说，它看起来会像这样：

(defmethod special-move-for-piece ::Pawn
  [this game-board start-location end-location]
  (let [curr-piece-color (::color (get-in (::tiles game-board) start-location))
        move-direction (into [] (map - end-location start-location))
        prev-move (last (::move-history game-board))]
    (cond
      ;; en passant
      (and (= (second move-direction)
              (if (= curr-piece-color ::white)
                1 -1))
           (= (abs (first move-direction)) 1)
         (= (:type (::piece-type (::piece prev-move))) ::Pawn)
         (= (apply max (map abs (map - (::end-location prev-move) (::start-location prev-move)))) 2)
         (= end-location
            (into []
                  (map +
                       (map (fn [x] (/ x 2 )) (map - (::end-location prev-move) (::start-location prev-move)))
                       (::start-location prev-move)))))
      (-> game-board
          (update ::tiles assoc-in start-location nil)
          (update ::tiles assoc-in end-location
                  (get-in (::tiles game-board) start-location))
          (update ::tiles assoc-in (::end-location prev-move)
                  nil))

      (and (is-valid-move-for-piece? this game-board start-location end-location)
           (or (= (second end-location) 0)
               (= (second end-location) 7)))
      (-> game-board
          (update ::tiles assoc-in start-location nil)
          (update ::tiles assoc-in end-location
                  (assoc (get-in (::tiles game-board) start-location)
                         ::piece-type (>Queen))))
      :else nil)))

我不会在这篇文章里为每个棋子复制粘贴走法，但为所有不同的棋子类型和特殊情况定义相关方法相当直接，我对代码最终的样子很满意。当你阅读这段代码时，它看起来真的就像有人把国际象棋的所有规则都写了下来，这正是让我感觉良好的地方，也让我觉得我们做事的方式组织得很好。

但现在，（对我来说）最重要的问题大概是：

这个库真的有帮助吗？deft 让我们的生活更好了吗？

我认为确实如此，原因如下：

deft 同时给了我们 protocols/records 和 multimethods/plain-maps 的特性，所以我们不需要决定哪种工具适合我们的用例。这就像减少了很多认知负担，因为我们可以使用一个工具，并相信它能很好地完成一切。
特别是，能够为我们的 protocols 定义 :default 方法分派是件好事，而且能够从 repl 重新加载 protocol 方法定义，而不必重新实例化整个棋盘（并清除当前位置），这非常棒
能够在我想要为特定类型定义方法定义时强制执行，这真的很好，而且有一种简单的方法来添加 Malli schema 也非常好

总的来说，我对最终结果很满意，我会说我们库的测试是成功的。

你可以找到完整的代码：

游戏在这里：https://github.com/sstraust/deft/blob/master/examples/src/examples/chess.cljs

库在这里：https://github.com/sstraust/deft

以及详细的视频讲解在这里：https://www.youtube.com/watch?v=lrofmFI1UJY

6. 宣布 Deft：一个用于 Clojure 和 ClojureScript 的类与接口系统

今天我发布 deft！这是一个用普通 map 和 Malli schema 替换 Clojure 现有类系统的库。

我花了大约 6 个月才真正彻底想清楚，并把设计做到恰到好处，所以最终发布它感觉很好。

库：https://github.com/sstraust/deft 视频教程：https://www.youtube.com/watch?v=dlW6YzwUZ-M 在 Hackernews 上：https://news.ycombinator.com/item?id=46590958 （请给仓库点个 star！）

简介：这个库源于我们对 Clojure 现有类型生态系统的挫败感。defrecord/defprotocol，以及 plain maps+multimethods，按照它们目前的使用方式，都会让 Clojure 程序从根本上难以组织和重构。

问题在于：

Clojure records 使用单冒号（无命名空间）关键字访问来查找 record 字段
Clojure records 不允许你定义抽象类，或依赖复杂分派行为的东西。
Clojure maps 极难固定下来并保持稳定。即使有像 Malli 这样的库，也很难声明解释“我能用这个东西做什么？”的接口
除非你对每个用例都极其严格地定义 Malli schema，否则在解构过程中很容易让东西脱节，因为漏掉的字段查找会返回 nil

目标是提供一种仍然使用起来很愉快，但在你想要的时候能真正固定行为的东西（同时仍然保持符合人体工程学且有趣）。

第二个目标是做出可靠且稳定的东西，并且（希望）容易在现有代码库中采用。来看看吧！

8. 如何在 Wordle 中获胜

这周我玩了第一局 Wordle，我 4 次就猜中了！

好吧，我有点运气，但这并不全是运气。在玩的过程中，我有机会思考了一些策略，也发现了一些我认为别人可能忽略的陷阱。

8.1. 不要猜已经是绿色的字母

除非你是想做出最后一次猜测来赢得游戏，否则你不应该在同一位置猜同一个字母。你已经试过了，所以再做一次不会给你新的信息。

你的“猜测”注定是错的，但当你真正去解谜时，你现在排除（或找到！）了另一个可能的字母。让我们看一个例子：

假设你有 B - A - _ - E - S，全是绿色。你只需要猜最后一个字母，但剩下的选项很多。在你还没在那个位置猜过的字母中，D、K、N、R、S 都可以。你可以逐个猜每个字母，但你很可能第一次猜不中，最坏的情况会花你五个回合。相反，如果你猜 D - R - I - N - K，一个你知道是错的词，你就一次性“猜”了每个字母，所以你保证能在 2 次内猜中（如果没有黄色，你就猜 S）。

8.2. 当你猜新字母时，把它们放在它们常出现的位置

就一会儿，把 Wordle 想得有点像二分查找。你的目标是用每一次猜测学到尽可能多的信息。如果你的猜测把问题空间一分为二（即如果它显示绿色，你排除一半可能的词；如果它显示黄色，你排除一半的词），那么你每次猜测（平均而言）学到的信息最多。

现在——你只能在一个位置猜一个字母，所以要么它在你选择的那个特定位置，要么它在其他四个可能位置中的任何一个。如果你想让这两种结果大致等可能（或尽可能接近等可能），那么你选择的那个位置最好真的很有可能，以弥补其他 4 个位置。

对于字母 'Y'，像 R - A - I - N - Y 这样的猜测（平均而言）比像 Y - E - A - R - N 这样的猜测让你学到更多。

8.3. 先猜常见字母

基本上和上面同样的逻辑。要么它是你猜的 5 个特定字母之一，要么它是其他 21 个字母之一。你想猜那 5 个最能将问题一分为二的字母。

更进一步，一旦你猜了几行，你想根据你已经有的字母，猜最常见/最均匀划分的字母。Q 作为第一次猜测很糟糕，但如果你已经有一个 U 了，那么也许……

8.4. 在每一步都思考可能的单词列表

记住，你的目标是用每个字母“一分为二”。如果你对空间中的单词有感觉/随机样本，就更容易选出最能精确划分那个列表的字母/位置。

9. 习惯的力量（书评第 1 部分）

Charles Duhigg 曾是《纽约时报》的记者，你可以在他的写作中感受到这一点。这是一篇现代科学报道，耸人听闻、鼓舞人心，而且常常极具误导性。

这本书应有尽有，从沙发土豆到超级明星的自助式转变，星巴克和Colts橄榄球队的成功，全都用习惯的力量简单解释。当然，习惯在每件事中都只起很小的作用。当然，每场橄榄球赛都有一点运气成分（甚至取决于风和天气）。但是——有人养成了好习惯，后来变得成功——砰——因果关系——搞定——问题解决。

抛开这些天马行空的结论，确实有一些真实的（而且是近期的！）科学研究在进行，而我们对习惯不断变化的理解既有趣又强大。对我来说，关键要点是：

习惯绕过了我们正常的推理过程（并且不像计划和短期记忆那样存储在同一脑区）习惯可以建模为触发——行动——奖励的序列。如果你缺少其中任何一环，就不会触发（或学会习惯回路）习惯可以潜伏很长时间，即使我们已经不再践行它们。不过别搞错，这本书意在带来转变。你能做些什么来改变你的人生，就像Peyton Manning那样？同样，这里的科学结论不一，但作者的观点似乎是：

习惯很难被遗忘，但如果你把它们拆解为触发——行动——奖励的生命周期，就会更容易。如果你能替换掉行动，但保持触发和奖励不变，你就能劫持你的坏习惯来学习好行为。如果你想做出转变性的改变，最容易的是把全部注意力集中在一个习惯上，然后其余的习惯很可能会随之而来。习惯可以是件好事。思考很难，决定做什么需要付出努力。如果某件事（比如决定晚餐做什么）需要脑力，你就不太可能去做，因为那份脑力劳动和实际做饭一样费劲。试着养成习惯，试着提前想好你要做什么，这样当你到了关键时刻，就不需要费力了。

10. 现代货币理论与你

像任何政治议程一样，现代货币理论并没有被完美地界定，人们常常根据自己的野心来调整它的定义。据我所能判断，它是这样的：

如果你是一个控制自己货币的国家，那么负债是可以的，你可以想印多少钱就印多少钱，只要不引起通货膨胀。

有些人认为，借助MMT的力量，我们有资金去资助我们最疯狂的希望和梦想，只要有人有勇气打开印钞机。免费大学、贷款报销、免费住房，我们可以一键支付一切，而且没有负面的长期后果。只要我们不引起通货膨胀，真的就没什么可担心的。

10.1. 那个大大的如果

问题是，那是个相当大的如果。如果你从一个错误的假设出发，你可以“证明”任何你想证明的东西。如果我们能印无限的钱，又不引起通货膨胀，那确实很棒，但这种事有可能吗？我们是怎么走到这一步的，为什么有人相信我们能这么做？

理论上，经济学基于供给和需求。如果每个人都想要苹果，但没有苹果可买，苹果的价格就会上涨。如果没人想要苹果，但每个公民都囤了100个苹果，价格（以及苹果的隐含价值）就会下降。

同样地，如果美国每个人神奇地拥有1200万美元，他们都会争相用这笔钱去购买同样有限的物资。许多人都想要三居室的房子，但房子并不会神奇地变多。还是同样的人在互相竞争购买同一套房子。为了从某个真正想要某物的人手中以1200万美元抢购到它，你也需要花费数百万美元。

从根本上说，人们想要钱是为了用它购买商品和服务。在全球范围内，如果每个政府都印更多的钱，但没有同时增加全球可用商品和服务的总量，你并没有增加每个人的实际购买力，因为每个人仍在竞争购买同样有限数量的商品和服务。只有当生产出的商品和服务数量也增加时，你才真正增加了实际财富。

10.2. 我们是如何走到这一步的

所以，如果美国明天开始印大量钞票，并承担大量债务，我们预期一切东西的成本都会大幅上涨。我们预期政府债券会大幅贬值，对吧？对吧？

然而事实证明，在2008年金融危机期间，美国确实印了很多钱，也确实承担了大量额外债务，所有人都预期会发生通货膨胀，但不知怎的，它就是……没有发生。市场很难推理，没有人真正理解为什么会这样，但人们提出了一些理论：

美国被认为是一个值得信赖的机构，人们需要一个安全的地方存放资金。世界金融体系已经如此深度投资于美元，以至于美国可以为所欲为。刺激法案推动了如此多的经济增长，从而抵消了通货膨胀。

10.3. 美国作为值得信赖的机构

好吧，那么，我们之前承担了大量债务，结果没事。我们印了真正天文数字的钞票，人们仍然信任我们是一个稳定、可靠的机构。每个人都相信美国政府会偿还他们，并且会用保值的美元偿还。

即使在美国经济引发的危机中，美国看起来仍是存放资金的安全之地，因为美国过去一直如此负责任，如此可靠。

所以——如果我们突然开始不负责任，比如，累积巨额债务并印钞来偿还，人们会永远继续借钱给我们，对吧？对吧？？如果我们不生产任何东西，我们可以永远印钞，人们就会白白给我们东西，对吧？

有一种观点认为，因为我们以美元借款，而美元是事实上的世界货币，我们永远不会陷入困境，因为我们可以印更多钱来弥补损失。但你认为，如果就实际物质商品而言，我们没有提供任何有意义的回报，人们还会继续借钱给我们吗？如果美国政府买走你所有的东西，却只给你纸，不给你任何物品作为回报，你认为人们还会继续使用美元作为他们的默认货币吗？

从技术上讲，我们可以通过印海量钞票来偿还债务，但从投资的角度来看，这本质上等同于违约。我们做出了承诺，但就商品和服务而言，我们没有提供任何实际价值来兑现那个承诺。

贷款违约之所以如此危险，是因为它会毁掉你的信用。如果你破产了，再想获得另一笔贷款就难上加难，因为人们不再信任你了。

同样地，即使美国在技术上没有对其债务违约，但如果它通过印更多的钱来掩盖，本质上也会产生同样的效果，因为人们将不再信任我们。

我们可以“兑现”我们当前的信任和影响力，但一旦我们破坏了这种信任，我们就不能再那么强烈地依赖它了。

10.4. 劫富济贫

这个论点大致是这样的：

富人有的是钱，而穷人没有钱。所以，如果我们多印一些钱，把它们给穷人，这就会降低富人手中钱的价值，实际上是从富人那里夺走购买力，再分配给穷人。

它以干净利落的方式，实现了人们本就追求的目标。

问题在于——富人的财富并不是以美元形式持有的。真正的富人知道美元未必稳定，他们持有房产、企业股票，甚至珍贵的艺术品。当你让美元贬值时，这其实并不会真正影响到很多富人，但却会伤害到其他人。

真正受到伤害的，是那些受固定15美元（或更低）最低工资约束的人。受到伤害的，是那些对投资不太了解、只是把所有钱都放在储蓄账户里的中下阶层。它帮助了负债的人，也可能带来一些其他积极影响，但对许多人来说，它更像是一种不稳定因素，而不是有益之举。

10.5. 刺激与经济成长

好吧，这里确实有一个真正的论点。其想法是——印钱是可以的，因为我们可以创造更多的商品和服务。如果我们明智地花钱——修建桥梁、改善宽带，我们就能为以前失业的人创造就业机会。更重要的是，这些新基础设施和支出将刺激进一步的经济增长。

如果我们每花一美元，就能产生N美元的经济活动（这种事到底怎么可能可靠地计算出来？），那么我们就不只是在印钱，我们是在印价值。

这是我喜欢的那类论点之一，因为它在逻辑上是一致的。如果我们生产更多的商品和服务，那么即使流通中的美元更多，也有更多的东西可以用这些美元来购买。如果它真的能创造那么大的增长，那它就行得通。

这里的挑战在于，这极其乐观。你的政府真的那么聪明、组织得那么好吗，以至于能创造出价值10万亿美元的价值？也许吧。我们有过辉煌时刻，我也希望我们能把它用好，但大多数时候事情并不会那样发展。

11. 完美的相机

每年，大约在假期前后，我都会为自己挥霍一次，买一件真正的好东西。隔离期间被困在家里，没什么可花钱的地方，但我一直很享受拍摄风景照。我们仍然不能去酒吧和餐厅，但我们可以开车四处转转，我们一直在探索新泽西州内及周边的公园。

今年我下定决心要买一台新相机。比我已有的那台稍微好一点，也许可以用来打印照片和大海报。

我在2018年12月买了我的第一台相机。我记得花了很长时间挑选，最终选择了尼康Z6。我真的很想要一台D850，但加上镜头后价格太高，无法考虑。我也考虑过D750，尽管我喜欢光学取景器的想法，但无反相机似乎是未来的趋势，而老式单反会让我显得过时。我还研究过其他品牌，但佳能当时还没有出色的无反相机选项，而且我不太喜欢索尼这家公司。

两年后，我又回到了同样的境地，花了很长时间来挑选相机。

在此期间，我还有机会试用了一台老式单反（D610），我非常喜欢它。图像质量更好（至少直出如此）。使用光学取景器是一种解脱。更重要的是，整个相机设计得如此周到，构造精良。每个按钮都放在恰到好处的位置，每当我需要时总能找到按钮。像白平衡这样在Z6上深藏于菜单中的功能，在这里只需轻点一下。他们甚至有一个功能良好的辅助灯，基本上解决了我所有低光对焦的问题。感觉就像每当我需要什么，伸手一探，D610就有答案。

这次，在疫情期间我花费很少，决定是时候买一台真正的好相机了。每个品牌/类型都在考虑范围内。我决定要买最好的相机，然后就不必再考虑升级它，至少很长一段时间内不用。

当然，我很快发现这并不容易。即使你有全世界的钱，不同的相机也有不同的取舍。图像质量最好的相机又大又笨重。有些相机技术上动态范围较低，但图像渲染美丽自然。无反相机有面部和眼部检测，但缺少那种出色的光学和机械感。

实际上，每台相机都给你不同的体验，不同的相机在不同的情况下是“最好的”。如果你在自拍，你需要翻转屏。如果你带相机去晚餐，你需要时尚轻便的东西。如果你在拍摄活动，你需要最可靠的性能和焦点追踪。

我肯定想要一个小巧的，可以带去和朋友们的游戏之夜，但我也想要一个（可能又大又重）能以最佳图像质量拍摄风景的相机。我很快意识到，对于不同的情况，我想要不同的装备，没有一台相机能完美适合我的所有需求。

综合考虑，我大致将我的拍摄情况归纳为三种：

照片漫步。我专门为了拍摄漂亮的风景照而出门。我想要愉快的拍摄体验和极致的画质。轻一点固然好，但我其实不太介意更重的相机或较慢的自动对焦。朋友和家庭回忆。这是我会带着去聚会和玩迷你高尔夫的相机。我不需要极致的画质，但我想要不引人注目且超级可靠的东西。我在意的是在任何情况下都能拍到可用的照片。如果埃菲尔铁塔前的全家福拍糊了，我们不会再来一趟，也不会花两个小时重新调整来拍出完美的照片。同样重要的是，如果是别人在拍，照片依然要好看。人像/自拍——这介于上面两者之间。你有更多时间来布置环境/携带合适的镜头，但你仍然想要相当可靠的面部/眼部检测。 4.1 竞争者

4.1.1 佳能

佳能生产专业单反和无反相机。

他们最新的专业无反相机R5是一款扎实的全能机型，据我所知，它在几乎所有情况下都表现非常出色。它足够快，能捕捉运动和野生动物，拥有非常好的面部/眼部检测，便于拍摄朋友/家庭回忆，并且有非常好（尽管昂贵）的镜头来实现极致画质。一个很大的加分项是，它甚至有一个翻转屏，这对专业摄影师来说可能不太有用，但对于把每个人都纳入全家福来说非常有用。

R5唯一真正的缺点是它非常昂贵，而且在拍摄视频时会过热（虽然我不拍8K视频，但拥有一台会过热的相机还是让我有点紧张）。部分挑战在于第三方RF镜头不多，所以你只能使用佳能非常好但非常昂贵的镜头。佳能的色彩以优秀著称，但我也听说R5/R6的配置文件比早期的佳能单反更平，这意味着后期可能需要更多工作才能获得非常好的图像。

他们还生产一款专业单反，很受欢迎，能产生扎实的直出结果，尽管它的动态范围较差，并且相比尼康同类产品几乎没有有意义的性能提升。

佳能还生产RP，它是R5的更小、性能更低的版本

4.1.2 索尼

索尼的A7R4拥有最高的分辨率和所有无反相机中最好的面部追踪。它被认为是一台技术上非常精确的相机，尽管在一些易用性功能上有所欠缺，比如好看的直出JPEG和良好的人体工程学。现在佳能的面部追踪和技术规格大多已经赶上，我认为它更难被证明合理，尤其是因为我本来就不太喜欢索尼。不过它便宜得多，尤其是考虑到镜头的成本。

索尼还生产A7C，搭配蔡司35 2.8是你能买到的最小巧、同时能获得非常好画质的组合之一。他们还生产Rx1R，分辨率更高，但缺少翻转屏和IBIS，以及RX100，它小得多，但加上1英寸传感器，缺少你对专用相机所期望的一些质量。

4.1.3 尼康

我有一台Z6，它的面部/眼部检测就是很差。差到我感觉没法完全依赖它。我拍过一些照片，当时看着就不对劲，后来才意识到是相机没对上焦。我甚至没法用单点自动对焦，因为摇杆移动对焦点的速度太慢了。

我还注意到，和我在D610上拍的照片相比，色彩平衡略有偏差，尤其是当我用转接的F卡口镜头时，同样的镜头拍出的同一张照片就是看着没那么讨喜。也许有办法在后期调回来，但我就是觉得D610的照片好看得多，也容易处理得多。

也许尼康在Mark II上修复了自动对焦问题。也许用上最新最好的Z卡口镜头并做些调整，色彩就正常了。也许不用转接环，自动对焦会更好。但到了这个地步，我就是不信任它们了。我真的很喜欢Z卡口镜头，只希望它们背后能有一台更好的相机。

相比之下，我用D610的体验就非常好。一台10年前的相机，性能却依然能跟上今天的标准。按键和人体工学正合我意。这不是什么新概念，而是一台经过充分迭代、坚固耐用的专业相机。感觉我需要的一切都被考虑到了、都提供了。而最重要的是：直出画质近乎完美。

D850是尼康最新的单反，是D610的下一代（严格来说，是隔了好几代）。它保留了大部分相同的设计和做工，使用同样的F卡口镜头，而且据我所知，成像方式也同样非常讨喜。它实际上少了设计精良的D610上的几个功能（比如更精细的白平衡调整和内置闪光灯），但作为这些小牺牲的回报，你得到的是分辨率高得多的传感器、更好的动态范围、更好的对焦点、推图时更好的色彩保留，以及更多。

和Z6不同，我信任D610，我知道如果我买一台基本同样的D850，就会得到基本同样非常好的照片（虽然希望还能再好一点点）。

我一直在等/盼着尼康发布D850的继任者，但根据更近期的D780以及其他近期发布的相机，我猜测：

他们大概不会大幅提高分辨率。至少，如果发布一台分辨率明显高于他们最新无反产品的单反，那说不通。他们大概会把无反相机上那套糟糕的面部和眼部检测移植到实时取景模式里。我其实更喜欢我D610上的反差检测。它可能慢，但至少可靠。加入相位检测也意味着传感器上多了些可能影响画质的东西。他们可能会加入机身防抖，我也确实很想要机身防抖，但这不算什么大事，因为我很多镜头本来就有防抖。 4.1.4 徕卡

我觉得徕卡就是那种品牌之一，人们买它就是为了搞清楚到底值不值得买一台徕卡。坐法拉利真的会顺畅得多吗？不试一台你永远不会知道。

玩笑归玩笑，我想到了一些人们可能想要一台的真实理由：

它们渲染得很好。这一点很难量化，尤其是当技术图表并不总能支持这些说法时，但有些人就是喜欢徕卡图像的整体渲染/美学感觉。它们看起来漂亮。好吧，对摄影师来说，这似乎不应该重要，但它确实重要，因为它影响你是否会随身携带它。如果你带着D5出现在皇家婚礼上，你看起来像狗仔队，但徕卡则时尚而有品位。你甚至可能把它作为着装的一部分，只是为了看起来有点潮。它们很小。你见过巨大的Nikkor 0.95 Noct吗？你见过它与徕卡noctilux的对比吗？noct稍微好一点，但你得到的是通常非常大的全画幅定焦镜头，却装在非常小的包装里。这意味着你可以随意携带，也意味着它更适合休闲环境。它们是旁轴相机。如果你想要旁轴体验，徕卡几乎是你唯一的选择。我不觉得这让我感兴趣，但如果你需要手动对焦旁轴，徕卡就是该去的地方。我喜欢徕卡非常小。对我来说，能随身携带它们，并且在不使用时它们不碍事，这很重要。不带巨大的单反相机出去吃晚餐，感觉更放松。

挑战在于，徕卡没有出色的自动对焦（如果有的话），并且完全缺乏“非专业用户的易用性”。它们是一款很棒的轻便度假相机，适合有趣的摄影漫步，但如果我去一个美好的家庭度假，我想要一张美好的家庭照片，而徕卡相机就是做不到。（Q2勉强可以）。

4.1.5 富士胶片

他们的APS-C系列相机很扎实（而且好看！），但我觉得它们不够小，不足以证明与A7C这样的机身相比在质量上的差异是合理的。他们还生产X100V，其旁轴风格非常吸引人，但有更小、更轻、图像质量更好的相机。

GFX系统是一场冒险，因为它有点不方便，但不可否认比任何其他实用系统表现更好。当其他制造商宣布100MP时，图像可能看起来更有颗粒感，但用更大的图像传感器实现这一点，你确实获得了多50%的空间。不仅如此，我可以说刚发布的GFX 100S是特别的东西。它不仅修复了原版GFX 100的人体工程学，不仅将性能融入一个微小的、单反大小的包装中，而且以GFX 100成本的60%来说，绝对是个便宜货。

我想要一个，因为我知道那种性能突破的相机可以保持自己的地位很长时间。就像他们制造了一台比他们绝对的中画幅旗舰好得多的相机，并且收费不仅低于他们自己的旗舰，还低于全画幅竞争对手的旗舰。D850在4年前推出时是件大事，但这是现在正在发生的大事，并将在未来很长一段时间内继续重要。

我不能完全为富士的色彩科学担保，因为我还没有像对待我的尼康那样把它们彻底测试过，但我听说过关于他们色彩科学的好评，而且他们的胶片模拟看起来真的很吸引人，至少从我筛选过的在线测试图像来看是这样。

GFX 系统的一大问题在于可用的镜头并不多。它现有的镜头确实惊艳，有些甚至被认为明显优于单反版本，但你只能使用富士提供的镜头，如果你需要某些特定规格，比如 14-24 2.8，那就没办法了。这是一个你买镜头和买机身同样重要的系统，所以你不能孤立地考虑相机，而要考虑它与你实际会使用的镜头搭配表现如何。

如果我入手 GFX 系统，我想要 32-64 f/4 和 45 f/2.8，这两支都是性能极高的镜头，不过我还是希望它们有真正的 24-70 f/2.8 等效镜头，以及一些焦段范围更大的其他选择。

4.2 做决定的时候

我知道，由于疫情，我基本上会有几个月到一年时间与正常的社交活动隔绝，所以随身带着又大又重的单反也没太大关系。我也不想成为那种口袋里掉出一百万台不同相机来应对不同场景的人。关键在于，用手机自拍完全没问题。你可以有一台好相机，但并不是每张照片都需要达到最高分辨率的画质。如果你只是想留下做煎饼当晚餐的美好回忆，更重要的是不要打断你想要捕捉的那个回忆。也许如果我买了一百万台相机，我会买一台非常小巧的，但那不是我现在的需要，而手机对于非摄影性质的照片来说是相当可靠的替代品。我对固定焦距的定焦相机也有点警惕，因为一旦你开始裁切，就失去了画质上的所有优势。

我想亲自试用所有相机，但同样因为疫情，我实际上没法去相机店。我可以在网上找到样片，但总是很难判断其中有多少是后期处理，有多少是场景光线和摄影师技术带来的。

考虑到这一点，只看大型、高性能的可换镜头相机，我缩小了选择范围。尼康 Z 和 A7R 系列被我排除，因为我认为它们已被佳能 R5 超越。5DMark4 也被排除，被认为已被 D850 超越。剩下的选项是：佳能 R5、尼康 D850 和富士 GFX 100s。

R5 拥有出色的 RF 镜头群，是一台均衡的相机，有翻转屏，还有非常实用的人脸和眼部检测功能。此外佳能以制造好用、易用的相机而闻名。问题是，在镜头方面，腾龙的镜头便宜得多，而且性能非常高（尤其是 35/1.4！），而 D610 实时取景中的人脸检测实际上非常准确且可用，尽管对于快速移动的拍摄对象来说太慢了。直出色彩也被认为比其单反版本略显平淡。我真正最怀念 R5 的地方其实是翻转屏，但我想如果我们真的那么需要拍合影，可以请别人帮我们拍。与 D850 相比，它还缺少大量按键和光学取景器的体验。

GFX 100S 是我考虑得最多的相机。搭配 45 f/2.8 或 110 f/2，它能提供任何实用相机中最好的画质，知道自己拥有最好的，感觉很好。如果你的照片看起来不如网上找到的样片，知道这不是因为你选错了相机，会让人感觉很好。在编程中，我们把调试视为“找出破坏软件的错误的根源”，而拥有最好的东西会让你的系统更简单，因为你需要检查的错误来源少了一个。你不必回到同一个地方用不同的相机再试一次，因为你知道那不是相机的错。它让你不再纠结于器材，而是专注于其他能造就一张好照片的因素。

虽然与 R5 有竞争力，但 D850 也是一台 4 年前的相机。以技术发展的方式来看，能有一台在过时前能用 10 年的相机是幸运的，而它已经走完了一半的寿命。相比之下，GFX 100s 不仅是新的，而且是开创性的，是技术上的巨大飞跃，似乎很可能会持续很长时间。你买入的是一个庞大、崭新且快速成长的系统，而不是一个正在慢慢被淘汰的系统。它也已经是第四次迭代，确实在细节上得到了关注，使其成为一个成熟的产品。它缺少竖拍手柄，但总体而言它非常完善，没有什么仍然笨拙或缺失的重要部分。

在 D850 和 GFX 100s 之间，决定是最难的，因为 GFX 100s 实在是一个太有吸引力的选择。

但最终……

我选择了 D850。对我来说最重要的一点是我喜欢使用 D610，不仅如此，我信任它。我不知道 GFX 100s 用起来会不会有趣，或者它渲染图像的方式会不会是我喜欢的，但我知道 D850 会，因为它和 D610 一样。我记得两年前买 Z6 之前，一些评测者告诉我它渲染得很好，自动对焦可用，但在我看来，他们大错特错。

GFX 系统可用镜头的缺乏对我来说也是一个大问题。如果你用 35mm 拍摄，然后裁切到 85mm，你根本得不到中画幅传感器的任何画质。如果你使用 GFX 系统，你就被困在区区 2 倍变焦范围里，这意味着除非构图恰好与你手头的那支镜头吻合，否则你拍不到想要的画面。

别误会，有些富士镜头很棒，但并非所有镜头都完美，如果我需要的东西缺失了，我就是拿不到。45mm、110mm 和 32-64mm 被大多数评测者（以及技术图表）认为近乎完美，但其他焦距并非如此。如果我想要一支超高性能的 35-150 呢？如果我真的需要我的 24-70 f/2.8 的长焦端呢？你不仅被困在购买昂贵的富士玻璃上，而且无法选择哪支镜头最适合你的使用场景。

即使焦距相同，选择也很重要。富士只有一支真正的饼干头，但它不是我想要的那种。我想要一支 28mm 饼干头，以及一支更大/更高性能的 50mm，但富士不提供这些。不仅如此，有些镜头的渲染方式可能不是我喜欢的。腾龙和适马都制造了出色的 35 1.4，但我喜欢腾龙的外观，我不想为了转到富士系统而放弃这一点。

我知道我在开头说过我愿意更换系统（如果Z6有货的话我肯定会换），但不用为了新镜头而折价换购是件好事，更重要的是，我已经做过功课，我知道我喜欢哪些镜头，也知道哪些镜头适合我需要它们做的事情。

4.3 大结局

我的D850几周前寄到了，它正是我想要的。它就像D610一样，只是对焦更快，分辨率更高（图像看起来甚至更清晰一点）。作为一件工程作品，它考虑得如此周全，设计得如此精良。它还像坦克一样坚固，看起来能经受任何考验。我真正怀念D610的只有自动白平衡内更精细的温度调整、播放模式下的专用润饰按钮，以及内置闪光灯。我也更喜欢把白平衡按钮放在相机侧面，而不是顶部靠近指令拨盘的位置，尽管它在D850上的位置仍然非常合理。更高的传感器分辨率有时会带来一点噪点，但我认为在缩图到公平比较时，它仍然胜过D610。

但真正让我惊叹、也是我没想到的，是D850文件在尝试编辑时表现得多好。如果你把D610文件提亮2档，它看起来会发白，你必须提高曝光和对比度来补偿，但在D850上我没有遇到这种情况。它们直出时大多相当，但一旦你尝试编辑它们，D850的色彩就是看起来更好，也更容易调对。

在图像质量方面，我感觉我买的是D610，但更好。我得到了同样的观感，既正是我想要的，又比以前更好看。它与我熟悉且已经非常满意的镜头完美配合。我喜欢通过光学取景器拍摄。

这是一台4年前的相机，但奇怪的是，我不认为它会在很长一段时间内过时。佳能和索尼的最新最强产品在图像质量上几乎没有提升（我实际上更喜欢尼康），我甚至不觉得它们明显更容易/更愉快地拍摄。我不认为索尼会很快淘汰它全新的Alpha One，而腾龙35/1.4与最好的无反镜头不相上下。它是一台4年前的相机，但它是我最喜欢的，我认为它将在很长一段时间内保持竞争力。

12. 相机镜头：我的包里有什么

相机镜头很贵。如果你拥有一台单反，你的镜头很可能比相机机身本身还贵。这是因为镜头往往是图像质量的瓶颈。如果你透过一扇模糊的窗户看，传感器有多灵敏都无关紧要。

此外，相机镜头有各种形状和尺寸。物理限制意味着你不可能有一支镜头包办一切。如果你的镜头有巨大的变焦范围，那么它可能牺牲了一些图像质量。你想选择适合你拍摄情况的镜头。

如果你想找到适合你的镜头，你应该先考虑你拍摄的情况，然后选择适合那种情况的镜头。除非你在摄影棚里，或者有一个非常有耐心的拍摄对象，否则你很可能不想临时换镜头，所以你想要一支能涵盖那种情况全部的镜头。

我的包里有什么？

5.1 人像镜头：Tamron 35-150mm f/2.8-4

大多数专业摄影师会携带两支变焦镜头，一支24-70 f/2.8和一支70-200 f/2.8。但用于人像拍摄时，这两支镜头都无法完全满足需求。85mm被广泛认为是“标准”人像焦段，但50mm甚至35mm也很常见。问题在于，人像拍摄所使用的焦距范围就像以70mm为中心的正态分布。为了拍出合适的照片，你需要不断在两支镜头之间切换。我曾用24-70拍人像，发现自己总是处在变焦范围的长焦端附近，常常希望能再多一点。

Tamron 35-150堪称完美，因为它的变焦范围中心也正是我拍摄人像所用范围的中心。它的变焦倍率（5倍 vs 3倍）比标准24-70略高，但它并非那种牺牲画质的超大变焦镜头。大多数实验室测试对它的评价与一些较老的70-200 f/2.8镜头相当，所以相比更标准的变焦镜头，你并不会损失太多。

此外，它相当快。它是可变光圈，因此在变焦范围的长焦端会损失一些速度，但35mm端的2.8与标准24-70一样快。这意味着如果你在室内没有闪光灯，它有时仍然可用。

没有真正面面俱到的镜头，但对我来说这已经是最接近的了。如果我要去某地一日游、不确定会拍什么，我经常会用它。缺点是它非常大（尤其是加上FTZ转接环时），对焦比一些原生Z卡口镜头稍慢、可靠性稍差，而且锐度和速度都略逊于优质定焦镜头。

5.2 暗光之选：50mm f/1.8 G

Ok, well, I'm currently looking to upgrade my 50mm to a different lens of the same type, either the 50mm f/1.8 Z or the 50mm f/1.4 Sigma Art. I bought it because it was cheap, and did something none of my other lenses had. It's not even sharper than my zoom lenses at it's only focal length of 50mm, but it does have one thing those zoom lenses do not: a maximum aperature of f/1.8. If it's dark, and you need light, a fast prime is your only option. Once you're already cranking your camera's ISO the extra stop over an f/2.8 makes a huge difference. A fixed length prime is the least flexible, but it's important when you need it. Also, most fixed length lenses are sharper than their zoomy counterparts, but not this one :(.

5.3 Lightweight Travel/Group Photos: 24-70mm f/4 S

I'm gonna be honest, the only reason why I own this lens is it was half off when it came with my camera. Don't get me wrong, it's still a good lens, but I probably wouldn't have gone out and purchased it on my own. What I like about this lens is that it's super reliable. It's a native Z mount lens on a Z body camera, and the autofocus just works better than any of the other lenses on the same camera. The image quality is also consistently good at f/4 throughout the zoom range, so much so that I don't have to think about it. If I'm going out for the day with casual people, this is the lens that I take. Most people don't want to wait while you fiddle with your settings, and most group photos don't care about artistic framing. The people care that you got the shot, the one where everyoen was smiling, and it didn't come out weird. If it's blurry that's really bad and you likely don't have that many do-overs. It's also super small on the Z body, and feels nicely balanced. Most travel photos I take are wide-angle anyway, because I want to capture the environment, and you're often in those situations where you have to pull the shot quickly and not mess it up. The lack of light can be inconvenient sometimes, but so far it hasn't been worth it to me to shell out for the much better (and much more expensive) 24-70mm f/2.8 S lens.

13. Why Many Primary Forecasts are Wrong

Ok, wrong might be a little bit too severe, but at the very least unfairly biased. I think most models underestimate Warren and Sander's chances of winning the primary because it evaluates the voting in every state as a single event, rather than viewing the primaries as a sequential selection process. In past elections, while the later states still matter, the early voting states have had special significance because they narrow down the pool of candidates by eliminating out candidates which seem unlikely to win.

Let's say you're a Democratic moderate. Even if you really really like Tulsi Gabbard, you're probably not going to vote for her, because you know that if you do, your vote won't matter. Since she's not going to run anyway, you might as well vote for Mayor Pete or Joe Biden. When the votes from the early states come in, they tell the people what candidates are unlikely to win. When a candidate does badly in an early state, people become less willing to vote for them and they become even more unlikely to win.

While eventually the race usally comes down to two or three, often closely split candidates, it's important to remember that primary elections are an unstable equillibrium, and it can be easy for things to snowball. Right now Biden is by most polling clear favorite to win the election, with roughly double the odds of the next major candidate. But it's important to remember that this is because Elizabeth Warren and Bernie Sanders split the progressive vote, and their policies and supporters are in many ways very similar. If one or the other starts to outpreform in some of the early states, they're going to start picking up all of the progressive votes, and start to become competitive in the states where Biden was heavily favored. While Biden could also gain some ground from early victories, he has less room to grow because the moderate vote is less split, and the other candidates to gain from like Mayor Pete, have some significant ideological differences.

14. The Wonky Math behind the Democratic Primary

Oh man, if you thought the electoral college was bad, you're in for a real treat.

On paper, it looks like primaries are mostly the same process. Every state gets "electoral college delegates", and the number of delegates for each state is the same as in the presidential election: two plus some extra porportionate to the state's population.

The thing is, the number of delegates is porportional to the state's TOTAL population, not the number of people that actually vote in the election. If California has 50 million citizens, but only 5 people actually vote, those 5 people have tremendous influence. In primaries, certain states are dominated by particular parties. That means even though Tennessee has 5 million elligible citizens, it only has 400 thousand voting in the Democratic primary. That means if you're a Democrat in Tenessee, you have much more influence than a Democrat from California. The state is considered large even though the number of Democrats actually voting is small.

7.1 Biden is Winning in States with Low Voter Turnout

Ever wonder why Biden seems so unpopular with so many voters, yet forecasts frequently predict him to win the election? Biden's best state's, according to 538: Alabama, Mississippi ,Delaware ,South Carolina, North Carolina, and Louisiana, are ALL low Democratic voter turnout states. Biden isn't actually that popular with the Democratic party overall, but it doesn't matter because he's disporportionately popular among the subsets of people that have the most voting power.

By contrast, take a look at the best states for Bernie Sanders: Vermont, Utah, Washington, California, Colorado, New Hampshire, all heavily Democratic states. Because he's appealing to more liberal states, and because his message resonates with certain groups of people, he's being disproportionately hurt by the electoral college relative to his popularity.

https://fivethirtyeight.com/features/biden-is-the-front-runner-but-there-is-no-clear-favorite/

15. What's Going on With The Impeachment

The impeachment trial, as it stands, is a little bit of a mess, with what feels like many muddled and ever-changing accusations, against a president who keeps doing new things to be accused of. Right now Nancy Pelosi orchestrated an impeachment vote in the house, but has stalled refusing to send a vote to the senate. Given all the confusion I'd like to take a step back to understand how we got here, and why it all happened the way it did.

Before anything, we need to understand that this is first and foremost a popularity contest, with a jury of the American public. There are legal rules, sure, but the people who are voting on impeachment are congressmen, and congressmen represent the desires of their constituents. You can see this in the correllation between congressmen's willingness to defend Trump and his popularity within their home state, as well as how their treatment of him changed as he rose in popularity within the republican party. In order to get him impeached, the Democrats need to convince the people that he should be removed from office.

8.1 The Russia Investiagtion

On November 8, 2016 Democrats were absolutely stunned. Despite all the polls from trustworthy sources like the New York Times*, an unthinkable candidate had won the election. There had to have been a mistake. There had to have been something deeply wrong, Democrats everywhere searched for an explanation.

Not believing that such a candidate could have won fairly, they blamed James Comey for unfairly reporting on Hillary's e-mails just days before the election. They blamed misleading polls discouraging Democrats from voting in an already "certain" election. And finally, they blamed Russia for interfering in our Democratic process, certain that for this to happen, rules must have been deeply and influentially broken.

There was a lot of evidence suggesting wrongdoing. Trump always seemed to have a soft spot when he spoke of Russia. There were the meetings in Trump tower. And Trump seemed to be doing everything in his power to kill the investigation.

The first weeks of Trump's administration were hectic to say the least. Trump picked fights with anyone and everyone. He struggled to assemble a cabinet and wound up leaving many key government positions unfilled. He seemed hell-bent on ignoring all rules and structure, as much as he possibly could. And finally, in a move that shocked many, he fired the person investigating him, FBI director James Comey.

Things moved quickly. Deputy Attorney Rod Rosenstien appointed a special counsel to replace Comey in the Russia investigation. Mueller seemed like just the man for the job, and over the coming weeks, his team gained momentum. Democrats saw not only mountains of evidence piling up, but real criminal offenses, with Mueller and his team reaching indictment after indictment. And Trump, although powerless to fire Mueller seemed to be doing everything in his power to kill the investigation.

The Democrats saw the way the investigation was going, and they saw the indictments lining up, and they made a crucial tactical error. Instead of zeroing in on the firing of Comey, the offense they knew he had committed, they threw all their efforts behind the Russia investigation, doing everything possible to stoke public excitement for a dramatic Mueller testimony.

They had a precedent from the Nixon investigation, one of the few issues on which Trump lacked positive sentiment within the Republican party, and what looked to be an undeniable act of treason. They thought the Mueller report was going to be a bombshell. That they were going to catch Trump red-handed, and that it would suddenly and dramatically sway public opinion. They were expecting something so severe that it would be impossible to claim impeachment was a purely partisan investigation. Even many Republicans were holding their words, waiting to see what the report described.

A week before the report's release, the Democrats made another tactical error. Instead of demanding Mueller first testify to the public directly, they allowed his report to pass, largely unquestioned, through Trump's justice department, and Attorney General William Barr. I don't know if they could have stopped Barr from publishing his letter, but they could have kept the tension, pushing people to wait for the bombshell that was the final report. Instead, they let the singular news story, the one they were building up for months, be not Mueller's report itself, but Barr's report on Mueller's report.

8.2 The Mueller Report

On March 24, 2019, Barr issued his letter to Congress. The verdict was "no collusion", i.e. the investigation did not establish coordination between Trump and the Russian government. Importantly, despite all the evidence in the report, Barr himself decided that Trump had not committed obstruction of justice, and attached his own findings, instead of the report's in his letter. Mueller himself described Barr's letter as a mischaracterization of his report, and in another mistake, Mueller expressed his discontent privately instead of immediately going to the public.

It was only after the full report was released, nearly a month later, that people began to realize what happened. Most neutral media organizations and fact checkers described Barr's letter to be intentionally misleading. Instead of "totally exhonerating" the president, Mueller had carefully layed out the case for obstruction of justice, and seemed only to not reach a verdict because it was not in the mandate for his report. In addition, instead of finding no evidence of direct collusion, he did suggest there was questionable behavior towards Russia.

By this point the moment had long since passed. Democrats had been hyping up a jarring news story, and what they got was a drawn out fizzle. There was a lot of dirt in the Mueller report, but Democrats didn't get the conclusive proof they claimed was lurking. They tried to pivot and push further, but having failed the first time, it looks like they were just grasping at ways to accuse the president.

If they had focused in on obstruction of justice, they would have gotten the president on an act they knew he had committed, and bad news from the Russia investigation wouldn't have broken their momentum. On the other hand, if they had spent months arguing that Trump had broken rules by firing Comey, and real evidence was found from the Russia investigation it still would have been the bombshell they needed to sway public sentiment and press further. This is again an instance where Democratic leadership was too confident and failed to plan effectively to minimize their downside.

8.3 Rebuilding a Case

In the months after the Barr's letter, the Democrats were frustrated and disorganized. They sensed Trump was doing something wrong still, and pushing the boundries, but they lacked a single rallying cry. If they had done so from the beginning, their strongest play would have been to rally around the firing of James Comey, but by now years had passed, and it would be hard to pick back up again.

Despite the lack of a central rallying cry Democratic voters were angry, and they were growing more angry with each new presidential offense. More and more moderate Democrats, long evasive, now publically voiced their support for impeachment. As primary season rolled in, all eyes turned to the candidates, who felt rising pressure from the left-most wing of the party. Unable to avoid the question in debate after debate, the candidates all lined up in support of impeachment. Only Nancy Pelosi and her closest allies held their breath.

8.4 The Ukraine Scandal

Finally, in September, news broke that President Trump asked the Ukranian government to investigate Hunter Biden the son of his chief political rival. Abuse of power to investigate a political oponent drew such a parallel to Watergate that it immediately set off alarm bells in politician's minds. Not only did they have more evidence of wrongdoing, but their anger had a central focus once again. Pelosi, sensing a shift in momentum, announced that she would begin the impeachment process. After an announcement from their extremely cautious, yet trusted leader, the rest of the Democratic party followed suit.

Why was Pelosi cautious for so long? I think it's because you only get one shot to announce articles of impeachment (or at least, if your first attempt fails, it makes your second attempt harder). I think she was saving it, waiting for a news story like this one to break, so that when something like this did come out, she could investigate it and apply pressure on it. Starting an impeachment proceding draws national news coverage, and she wanted an event that the American people would see as definitely wrong, something that was worth spending her news coverage on.

The impeachment process also makes it easier for the Democrats to carry out a formal investigation. This means that the democrats got to learn about the Ukraine scandal in more detail, and potentially uncover even more damaging information. In addition, waiting for so long gave some kind of additional credibility to the investigation. It sends the message that Pelosi feels "we don't want to do this, and we won't unless we really have to, but as it turns out we really have to."

In addition, Pelosi learned from the mistakes of the Russia investigation. Despite gaining such a powerful rallying cry, she didn't make the impeachment entirely reliant on proving coordination with Ukraine. She included an article "Obstruction of Congress", about Trump's efforts to block investigation, which relies almost entirely on publically available knowledge. As such, it can't be easily disproven, so Democrats can keep pushing in that direction no matter what other information comes out.

8.5 The Threshold of Popular Support

Despite all this, Nancy Pelosi is stuck. One of the reasons why she stalled on starting the impeachment process for so long is she knew that she wouldn't be able to carry it through to completion. At least not through the Reupblican controlled Senate, where Mitch McConnel has promised a speedy acquittal. And yet, she still wanted to start the impeachment process so that she could draw public attention and promote an investigation. So, she drafted the articles of impeachment, got them passed in the house, and then, did the only thing that she could do. She stalled. Hearing Mitch McConnel's vow, she refused to send the articles of impeachment to the senate. This means that Mitch can't kill the impeachment, and she gets to keep up the pressure until the tide turns in her favor.

What gives? Trump is an unpopular president. Just a month after he took office, over 50% of people disapproved of his presidency, according to polling tracked by 538. As of this moment, more Americans support impeaching Trump than those who are against it. Congressional votes are largely determined by the opinions of their voter-base. So why can't Pelosi get the votes she needs?

Well, impeachment is very popular among Democratic voters, but as you might have guessed, it's not very popular among Republican voters. And the thing is, it's Republican senators that need to vote for impeachment for the thing to pass. 50% of people might want Trump impeached, but that breaks down to like 80% of Democrats and only 10% of Republicans. Republican senators likely won't support impeachment unless a majority of their own party supports it. That means Trump has to be really unpopular.

Given the unwavering support of his base, it's not clear what it would take to move the needle on impeachment. Polls show an uptick in support for impeachment after news of the Ukraine scandal broke, but only a small uptick, and one that still gives impeachment less than 10% support among Republicans. If anything, the history behind the impeachment proceedings, and the haphazard way in which it all went down made it much harder to impeach Trump because it gave wiggle room for his most ferverent supporters to believe it was all just a partisan mess. I don't think it'll go anywhere in the near future, because if Pelosi is smart, she'll hold her cards and continue to prevent a Senate vote, and if Trump doesn't make any big mistakes, he likely won't lose enough popular support to be impeached.

I think going forward, the stalemate will continue. Pelosi doesn't have the votes, and shouldn't risk a clean shot at impeaching the president. Senate Republicans might try to entice her with the promise of additional testimony in the house trial, but I think Pelosi would be stupid to take it. I think Pelosi is going to wait for the next big bombshell, and then pull the trigger whenever the momentum swings.

16. Treating Cancer with Chemo (Part 3)

In this section, we now look at the specific drugs we would need to put the ideas in Part 2 into practice. We have a tremendous advantage here because we are not developing new chemicals. All of the drugs listed have already seen clinical use. What we'd like to do is, send a signal that tells all the cells in your body to start dividing, and then send a chemotherapy drug which kills any cells that are still dividing. Your body has many types of signals which tell cells when to grow and divide,

notes: platelts come from Megakaryocytes which come from hematopoietic stem cells

I found the paper that has this idea https://www.ncbi.nlm.nih.gov/pubmed/8839398

17. Treating Cancer with Chemo (Part 2)

In the last section we looked into what types of cancer treatments are out there, and, from a research perspective, what areas hopefully have the most low hanging fruit. Due to cancer heterogeneity, and the problem of targeting undetectable or microscopic tumors, black-box chemotherapy methods seemed like they would yield the best results. I wrote down the definition of our "black box" and narrowed in on one property, that cancer cells divide regardless of external signaling.

Many drugs already target this pathway. Certain drugs attack cells which divide more rapidly, intentionally causing damage to cells during the process of cell division. In theory this will cause cancer cells to die because they will be more likely to die than the normal cells.

The problem is, this also kills healthy cells. Some cells, such as bone marrow cells, divide rapidly and, some cancers don't even grow that quickly. Some cancers grow at a normal rate for cells, they just don't stop growing when they're supposed to. The problem is that what you want to measure is not the cancer's rate of growth, but it's responsiveness to external signals within the body.

So how can we target this? How do we identify cells which don't respond to signals?

Well, instead of targeting cancer cells, we can send signals to identify healthy cells. We know that the healthy cells will respond to the signals and the cancer cells won't. By targeting everything else, we can measure when something doesn't respond to the signals that it's supposed to, and then go after it. Instead of attacking cells that divide quickly, we can tell all of the cells to stop dividing, and then kill all the cells that still divide. The cancer cells won't listen, but the normal cells will, so they won't get the damage that usually comes with intensive chemotherapy.

What's completely wild about this to me is that people are doing this already, but not on the cells that actually matter. We treat hair loss. We can help people not lose all their hair who are going through chemo by having them apply ice packs to the top of their head while they're receiving treatment. This works by slowing the division of the cells around your hair follicles, so they won't actually get killed and fall out while you're getting treatment.

In the same way that we treat hair loss, we can tell the cells in your bone marrow to stop dividing as quickly while the chemo is active and thus drastically reduce the side effects. Furthermore, we'd be able to use drugs that weren't previously available because even though they killed the cancer they were otherwise too toxic to the human body. Even better, we already have the tools to do this. We already have drugs which slow the growth of bone marrow cells. We just have to apply them in the right way.

18. Treating Cancer with Chemo (Part 1)

Cancer treatment is something I've thought about a lot recently, and the more I've studied it, the more I've seen that it's an interesting and complex problem. At it's core a cancer is a group of cells whose genetic code has mutated such that they divide uncontrollably, in a way that cannot be properly regulated by the body. Cancer cells, in contrast to benign tumors, also have the ability to sustain their growth, and to invade other parts of the body. If the cancer cells grow too much, they can "crowd out" other bodily functions, by having large tumors that press against vital organs, or "replace" other healthy cells.

The challenge with treatment is that cancer cells, unlike bacteria or viruses, look remarkably like healthy human cells. It's difficult to kill the cancer cells without accidentally killing the normal cells. As a result, the main treatment options for cancer are:

Surgery: Cancers typically grow as a cluster of cells in the same physical location, called a tumor. One way to treat this is to just cut out the tumor. This is good because it can quickly and fully remove the entire tumor, but bad because it might not be in a place you can safely reach with a knife, and bad because it doesn't catch it if the cancer spread without your knowledge.
Radiation: Radiation zaps the cancer with high intensity beams of light. Think a really powerful microwave pointed directly at your tumor. This is good because it kills cells in places that aren't easy to reach with a knife, and can cover a wider area than would be safe to cut out, but bad because it might not kill everything in its beam and again, it won't catch the cancer if it spreads.
Chemotherapy: This is a broad term that refers to using chemicals to kill, or otherwise harm the cancer cells. Since this refers to many different types of chemicals, which act in many different types of ways, it's hard to give a one-size-fits all explanation. One type of chemical which is fairly common essentially tries to kill cells which are dividing very quickly or haphazardly, hoping to target the cancer cells unctonrollable growth. Chemotherapy is great because unlike radiation or surgery, it can attack cancer cells anywhere in the body, meaning that if the tumor had spread to a small undetectable cluster of cells, chemotherapy would still fight it. The downside of chemotherapy is it's not always very good at determining which cells are cancer cells. This means it can kill healthy cells all over your body, most notably in the bone marrow, which tends to replenish quickly.

There are a few other types of treatments, such as immunotherapy, which I'll skip for now as largely niche (but growing) fields.

I'd like to focus here on chemotherapy because, while currently surgery and radiation are often necessary, because they are unable to attack small groups of cells, I don't believe that in the future, anything more than incremental progress will be made. Whatever the solution is will likely have to be some sort of medicine because we can't physically target something we don't have the ability to detect.

Medicines that treat cancer (even including immunotherapy) are hard to make because it's hard for anything to classify whether or not a cell is cancerous. So, in order to treat cancer, we need to solve the classification problem, build a model to predict whether or not a cell is cancerous, and then encode it on a macroscopic scale. The more accurate our model, the more likely that the drug will kill the cancer without being otherwise fatal to the human body.

We can approach this classification as a "black box", i.e. the cell is a generic thing with certain properties which we can't see into. Or, we can think of it as an open box, i.e. the mutated DNA of a cancer cell causes these specific chemical reactions which, eventually cause the cell to divide uncontrollably. With open box models, we have a tremendous amount more information that we can use to classify the cell as dangerous, and it seems like this would be intrinsically easier, but this information comes at a cost. Cancer is a name for a disease that can occur in many different ways and for many different reasons, often exhibiting significant heterogeneity within a single tumor. If we treat one specific pathway of chemical reactions, we'll only solve the problem for those specific cells, and we'll miss out on all the different types of cancer that are possible.

I'd like to think about this problem as a black box problem because in addition to the curse of heterogeneity, it's also just better suited to my background. Treating the cell as an open box generally means lab work with equipment I don't have access to, and at best a 5-10 year trial period before a new chemical gets into production. It's my hypothesis that there are enough building blocks that are already well studied, that if we put them together in just the right way, we'll get a better result.

So let's take a look at the black box. I took a look at the definition of a cancer cell. It boils down to roughly:

The cells grow and divide regardless of what body signals them to do
They don't die when they're supposed to
They can invade other parts of the body
They get the rest of the body to support their growth (encourage blood vessel construction)

I'd say 2 is almost impossible to go after as a black box, since you can't ask a cell whether it will die without killing it. 3 seems similarly difficult because at best it can only attack spread, and not the original tumor, and because it's hard to ask a cell where it originally came from. 4 seems promising, but again has the problem that it likely won't cure tumors of smaller than a certain size. So, all things considered, I'd like to take a closer look at 1, that cancer cells grow and divide regardless of the body's signals.

19. The Importance of Doing Nothing

This morning I woke up, a little on the later side, and didn't have anything important to do. I didn't have work, and I didn't have chores, just had to eat breakfast, and be out the door by noon. I had 2 and a half hours, so it should have been easy.

With so much time, and nothing, really, to do, I started browsing the front page of reddit. I thought maybe the act of reading, or looking at something would wake me up a little. 30 minutes passed. This was no big deal, as I had all morning, really, but I felt like I wasn't quite done yet, so I kept going.

By 1130, I was still searching for something initeresting, and I still hadn't found what I was looking for. I knew I was wasting time, and I knew that I wasn't going to feel fully satisfied at the end of it, but it always felt like the next two or three minutes would make me feel a little bit better, and that little time wouldn't be a deal breaker. By the end of it, I would click on a YouTube video and only watch the last thirty seconds of it, because in truth I didn't really want to watch the video, but I wanted to feel like I was going to find something new and entertaining. I didn't really feel like I was thinking at all, or even that I was enjoying what I was doing, but I wanted to see something. You can probably guess that I rushed the quickest breakfast (read: two bananas), and was out the door 20 minutes late.

Whenever I mess something up, I ask myself how I could of done better. In this case it seems pretty obvious. I could have just not wasted 3 hours scrolling around on the internet. I could have looked at Reddit for only an hour and a half, made myself a delicious breakfast, and still left on time.

But in practice, it's not that simple. That's because what you do with your time affects your ability to think and make decisions. If, after 90 minutes, I took a break to really sit, and think clearly about what I wanted to be doing, I would have realized I still wanted to breakfast, and that I wanted to be on time. But because I was watching videos, and because I was constantly blasting my mind with different signals, I never had a moment to really process what was going on.

Not only that, I noticed even after I left my apartment, after I had already stopped looking at a screen, I was still left with that same mentality. While I was walking to the train, I still felt this impulse to play chess or read the news. I wasn't thinking about the rest of the day, or about things I wanted to learn, or things I really cared about. For most of the afternoon, my head was still overloaded, and when I went to think, what came out were random memes and stories. I had given myself so much new information to process, that even after I was done looking at it, it still crowded out my other thoughts. It's not just about the moment, wasting your time does damage, and it's important to recognize what damage it's doing.

Maybe the videos made me feel happy for a half hour or so. Maybe I even learned a tiny bit, about news, or life advice, or something that might make good conversation. But I think I would have been better off if I had done, really, absolutely nothing. I would have been better off if I just sat down in a chair, and just waited. When I do nothing, it gives me the mental space to process longer-term thoughts, to prepare for my day, and to figure out what I really, genuinely want to be doing.

20. Why I Support Citizens United

Most people I know really don't like Citizens United. For those who aren't familiar, Citizens United was a supreme court decision that essentially let corporations and wealthy individuals funnel unlimited amounts of money into American politics. Not only that, it let people donate to certain types of political causes with little to no transparency or oversight. The people I know who don't like it view it as letting big money buy elections and spread corruption in American politics.

We have anti-bribery laws (which the courts have upheld). We have campaign finance laws (which the courts have upheld). So, what makes the Citizens United ruling different?

The Citizens United ruling applies only to campaign advertisements (not general campaign contributions), and only to money that is spent "independently", i.e. without talking directly to the candidate or political party. This means that if I'm Exxon Mobile, I still can't write Mitch McConnell a check for 10 million dollars. I also can't work with Mitch McConnel to film a TV ad for his upcoming election. But if I decide that I really like Mitch McConnel, and I don't talk to anybody, and I just pay for an ad telling everyone how great he is, then nobody can stop me.

As experience has shown, advertising can make a huge difference in the outcome of an election. If someone is allowed to spend an infinite amount of money on advertising, they, as an individual can have a massive influence on the outcome of an election. We have anti-bribery laws, but if someone can use money to ensure candidates with certain political views are elected, aren't the effects the same?

I like to think of this by considering the role of a news organization. We need some news organizations discussing American politics in order to keep voters informed, so that they can better understand the issues and decide who to vote for. Along these lines, it's even important to have news organizations that debate different topics, and to have editorials which discuss their own opinions because it's important for people to understand the reasoning behind the legislation, and get a sense of why or why not something is a good idea. Especially for traditional media outlets like newspapers and television, It's nearly impossible to publish editorials or simply report the news without incurring some sort of bias.

If you wanted to start a new cable news channel, you'd have to pay for a studio, for cable companies to distribute your broadcast, and to advertise your broadcast to others. Your news broadcast might be extremely biased, because, as we've already discussed, it's impossible to regulate bias in news organizations. You might not want a long-form news broadcast, so instead of paying for an entire television channel for an entire day, you might want to only purchase a slot that's the length of your show, or the message you want to publish. Separately, you might also want to be able to advertise your show (as news organizations are able to advertise), and in doing so accurately describe what's in it.

So, the question is, where do you draw the line? What's the difference between paying to broadcast an editorial piece and donating directly to a political campaign? Well, I think making sure that the broadcast isn't part of (organized by) the political campaign itself is a pretty fair place to draw the line.

21. Camera Settings

When I got my first DSLR, I opened up the settings menu, and found it loaded with options: active-d lighting, vignette control, auto-bracketing, ambient lighting, and much more. It took a while to sift through all the options, but after assigning some reasonable defaults (use full resolution, turn on vibration reduction when available, etc.), I found that despite all of the options, there were really only four dials that effected the raw image. The rest were either only in post-processing, or just different ways of twisting those original four dials.

Despite all the complexity, the only four dials you have on your camera are:

Exposure

Your camera has a sensor in it. When you take a picture, the camera opens up and lets light into the sensor. The longer the camera opens up, the more time light has to hit the sensor, and the brighter the overall image.

This comes from a time before people had digital cameras. When people used film, each wave of light would cause a chemical reaction on the film, so letting in waves of light for a longer period of time would cause more chemical reactions, and all of the individual waves of light would "add together" to form the overall image. That's why if you move a camera around while the film is exposed, the image comes out blurry.
Focus Distance

In front of the sensor, your camera has a lens. The job of the lens is to take in all of the light from the outside world, and bend it, so that the light is pointed at the sensor. Typically the outside world is larger than the size of the sensor, so the lens bends the light toward the center, with the light kind of following the shape of a cone. If the lens bends the light correctly, the square of the outside world that you want to capture will hit the image like a bunch of parallel beams of light, and you'll project a much bigger image onto a much smaller sensor. However, if the cone of light is too short, or too long, instead of hitting the image like parallel lines, the beams of light will get criss-crossed. Instead of one exact point on the outside world corresponding to one exact spot on the sensor, it might miss, and send some of the light kind of nearby, causing the image to be blurry. The correct focal distance is different for objects at different distances from the camera, so if you make nearby objects in focus, you make faraway objects out of focus.

Long story short, if a part of an image is not in focus, it looks blurry. You get to choose a distance away from the camera such that objects at that distance are in focus. The further away an object is from the focus you chose, the more blurry it looks in the photo.
Aperture

Typically, there's a physical shutter that opens up when you take a picture to let light onto the film or sensor. Aperature refers to how big of an opening there is when the shutter is open. If there's a really big hole, it lets in a lot of light, but if there's really small hole, it only lets in a little bit of light. Also, if there's a small hole, the cone of light (from the focus section) is skinnier, so the beams don't get criss-crossed as much. This means that objects that aren't at the focus distance don't wind up being as blurry, because there's less interference. If there's a big hole, the cone is wider, so only objects at a specific distance are in focus, and everything else comes out blurry. This can be useful in taking portraits when you want to emphasize an in-focus person against an out-of-focus background.
ISO

How sensitive your camera sensors are to light. High ISO means your camera registers a lot of input from a small amount of light. Most cameras are only able to get accurate readings up to a certain level of sensitivity, so bumping your ISO too high can result in noisy/grainy images.

So why do cameras have so many other options? Well, taking photos in the real world it isn't always easy to quickly and accurately adjust these four dials to set up for the shot you want. Want to get that monkey in focus? The one that's swinging across the jungle? Good luck twisting your focus knob and trying to keep up with it. You'll probably want your camera's autofocus tracking. Want to take many photos in a row, with different levels of exposure? There's a setting for that. It's not enough to just have access to those dials, you also want convenience tools that let you quickly choose how and when to take a photo.

In addition, even though it doesn't effect the raw image, many cameras have built-in post-processing to adjust for things like ambient lighting. While for more serious shots, you'll probably edit the raw files in a program on your computer like photoshop or lightroom, it is convenient, visually to get quick feedback on what the image might look like, and for those of us that are lazy out there, can be a quick way to produce reasonable quality images.