如果你重复某事，人们更有可能相信它。

This isn’t speculation, and it’s not just some old saying. It’s a real phenomenon well established and extensively studied in cognitive science. It’s known as theillusory truth effect:听到或读到一种说法，尤其是反复地听或读，会让你更容易认为它是真的。It was first documented in a1977 publication作者:林恩·哈舍尔、大卫·戈德斯坦和托马斯·托皮诺。自从这项开创性的工作以来，大量的进一步研究都重复了这种效应。The effect of repetition on apparent truth has been found forfake news headlines, it occurs with bothplausible and implausible claims, and it appearswhether the claims come fromreliable or unreliable sources.

If you’re hoping that greater knowledge or intelligence would counteract this effect, you’ll be disappointed: a 2015 paper found just as much shift towards believing repeated statements that wereknown to be false2020年的一篇论文发现，认知能力不会显著改变这种影响。这并不是说没有什么能驱散你从一遍又一遍地听到的东西中获得的真理的幻觉。如果你在人们第一次听到或读到某句话后马上告诉他们它是假的，效果就会减弱。And if you repeat a false claimtoomuch, people might see the repetition itself as an attempt to persuade them, and then belesslikely to believe the claim you’re ‘selling.’ Still, the only condition that seems to completely nullify the illusory truth effect is extreme and obvious implausibility: participants in one study weren’tanymore likely to believe statements like “the Earth is a perfect square” after repeated exposure to them.

为什么重复某件事会让人们更容易相信它?仅仅是听到或读到一个陈述与它的真相并没有一个非常一致的关系。有很多错误的陈述——不仅在心理实验中，而且在宣传网站上，在广告中，在人们每天告诉你的关于你自己和他们自己的小谎言(甚至是“白色的”)中。We live in an informationally rich environment, but one in which a lot of incoming ‘information’ actuallymisinforms. We know to be on our guard against this a lot of the time. Weknowthat a lot of what we hear is false. But then why does merely hearing something make us feel it’s more likely to be true—even ifwe know it to be false?

Most psychologists think the illusory truth effect reflects “processing fluency.” In other words, people tend to believe statements more readily if those statements are easy to process. One way something gets easier to process is repeated exposure: if you’re really familiar with some statement, it’s easier to process it when you hear it again. So if you hear something repeatedly, you’ll be more likely to believe it. And even if you don’t get all the way to believing it, you’ll rate its likelihood of being true more highly.

但这就是统一和解释可能产生分歧的地方。把虚幻的真相效应和处理流畅性效应统一起来是一回事，从而把它放在一个更广泛的现象的背景下。It’s another to explainwhythe illusory truth effect takes place at all. Even once we’ve unified the illusory truth effect with other processing fluency effects, we can request an explanation: why on earth should increased processing fluency affect belief in this way?

We could try another tack. We could try making sense of the illusory truth effect by placing it alongside other heuristics that affect human reasoning. For instance: as per theavailability heuristic,如果某个事件是你很容易想到的，你就会判断它更有可能发生。This and many other such heuristics were brought together in 1974 by Amos Tversky and Daniel Kahneman, and later summarized by Kahneman in his 2011 bookThinking, Fast and Slow.

Again, though, unification is not explanation. We can ask why we use any of these heuristics in the first place. The explanations given usually refer to our current environment, or an environment in which humans lived during our species’ evolutionary history. In the first kind of explanation, you could say (as Tversky and Kahneman did) that the heuristicusuallyleads to good effects in our environment, and these benefits are significant enough to outweigh any potential negative effects. In the second kind of explanation, you could say that the same pattern appeared in environments that adaptively shaped our thought.

But each of these explanations is dissatisfying too. It just doesn’t seem plausible that ourcurrent环境倾向于相信重复的事情，考虑到有多少错误信息会误导我们购买某些东西，为某些人投票。至于塑造我们物种的环境:真的很难证实关于这些环境的任何假设，尤其是那些涉及在相信重复陈述和获得其他形式的效率之间进行权衡的抽象环境。(关于我们进化历史的假说更容易证实，通常涉及具体的物理细节，比如我们祖先吃的食物类型。Even so, we’re still confined to studying the bodies of a small handful of long-preserved dead ancestors.)

我仍然对虚幻的真相效应感到困惑。Belief just doesn’t seem to be thekind of thing这可以通过暴露来实现。How on earth could a state evencountas a genuine state of belief, if you can get into that state by mere exposure to a claim? If a so-called “belief” can be put in place just by repeated hearing or reading, I might question the claim that the state in question really is a belief. That’s how strange it is to think that belief could be created by repeated hearing or reading: I might sooner give up the idea that it’s belief at all than accept that it can be created thus.

So I don’t have a solution to the puzzle that the illusory truth effect has raised. What I do have is persisting puzzlement. Let’s not jump to quick, shaky conclusions to try to eliminate that puzzlement. Sometimes it’s worth sitting with the strangeness of something for some time.

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