Before we can answer the question, “Is intuition a guide to truth?” we’ve got to get clear on what exactly we mean by “intuition,” and particularly by the philosopher’s use of this term.

The colloquial sense of intuition is something like an instinct or premonition, a type of perception or feeling that does not depend on—and can often conflict with—conscious reasoning. Our 2012 show “Gut Feelings” with psychologist Gerd Gigerenzer deals with these kind of intuitions, and the role they ought to play in important decision-making.

But there’s another, perhaps less-familiar, sense of “intuition,” which is the kind that philosophers often rely upon, and these are more caught up with conscious reasoning than intuitions of the "gut feeling" variety are. Let’s call this second kind, “intellectual intuitions.” Philosophers often try to use "intuition pumps” (to borrowDaniel Dennett’s term) as a way of defending a particular philosophical analysis of a thought experiment. Let me give an example.

Probably one of the most famous thought experiments in philosophy, inspired by Descartes’ evil demon, isHilary Putnam’s “Brain in a Vat.”在这个装置中，一个活的大脑被从身体中取出，放入一个装满营养物质的大桶中，并连接到一个超级计算机上，这样它就能以与正常的具身大脑完全相同的方式受到刺激。然后有人会问:你怎么知道，仅仅基于你的经验，你是否就是这样一个在缸中脱离实体的大脑?考虑到我们不可能把一个人的大脑取出来放进罐子里，来找出他们的经验是否有明显的不同，我们所能做的就是思考这个情况并形成直觉。

As a philosopher, Putnam is rather fond of using these kinds of thought experiments to elicit certain intuitions, though, I have to admit, he usually elicits the "wrong" intuitions in me. In the case of the brain-in-a-vat, the intuition we aresupposedto have is that there would be no detectable difference between the experiences of the brain, suitably hooked up and stimulated, and the experiences of a fully embodied person moving about in the world; hence, we cannot escape the radically skeptical conclusion that, for all we know, our perceptions of the world could be completely illusory. (Putnam actually comes to an even more radical conclusion, namely that brains-in-vats couldn't evenentertainthe thought that they might possibly be brains-in-vats, but we'll leave this aside for now.)

为什么认为这样的直觉是可靠的呢?如果你不认同“正确”的直觉呢?In the brain-in-a-vat thought experiment, you might share Putnam’s intuitionifyou already endorse a theory that reduces perceptual experience to neuronal processes. But what’s the evidence for that view? Varioustheories of embodied cognitionrefute this kind of reductive approach to perception (and its corresponding interpretation of the brain-in-a-vat thought experiment). So, if some version of embodied cognition is correct, then Putnam’s intuition that we wouldn’t be able to tell the difference between normal embodied experience and envatted brain experience would just be plain wrong.

不管你对这个特定的思想实验有什么看法，更重要的一点是，诉诸直觉似乎是一种做哲学的坏方法。首先，我们的直觉经常冲突，在这种情况下，我们如何决定谁是正确的?此外，当我们的直觉不一致时，通常是因为我们有不同的理论承诺，而这些先前的承诺提供了我们倾向于在哲学上发现的“直觉”。”

但是，即使我们总是认同我们的直觉，为什么要假设它们真的能提供关于世界的信息呢?当然，这个世界上有很多与直觉相反的真理。举一个非常简单的例子:如果你从一幢高楼上扔下一根羽毛和一个保龄球，你认为哪个会先落到地面上?亚里士多德和其他许多人给出的“直观”答案是，较重的物体会比较轻的物体下落得更快。但是，正如伽利略后来证明的那样，事实证明亚里士多德和他的同伴是错的。

This case highlights a big difference between science and philosophy: scientists, like Galileo, maystart offwith an intuition, but they never treat their intuitions asevidencefor anything. Instead, they go out and test them, and it’s thedatagathered in their experiments that counts as evidence, not the intuition that prompts the experiment. Philosophers, on the other hand, like to sit in their armchairs and come to all sorts of conclusions based on intuition. But why shouldanybody把他们的直觉当作任何事情的证据，而不是他们自己的想法?

One problem with simply dismissing intuitions in philosophy is that, for some areas of philosophy, intuition seems like an indispensable tool. Take moral theory, for example. How do we develop a good moral theory if we don’t start off with at least some intuitions about what is right and wrong and go from there? For example, we're often told as children that we should never tell a lie, but intuition might sometimes conflict with this moral prescription. Imagine you’re in Nazi Germany and you’ve hidden your Jewish neighbors in the attic. The Nazis come, demanding to know if there are any Jews in the house. What does your intuition tell you would be the moral thing to do? Lie to the Nazis, or tell the truth?

My initial response to this kind of thought experiment is this: if your intuition says to tell the truth, all that proves is that you’re an idiot. I mean, why go to all the trouble of hiding your neighbors in the first place if you’re only going to give them up as soon as the Nazis come knocking? Of course you should lie!

Granted, this snarky response slightly misses the point, which is that we have to use intuition to figure out the right way to act, and from there we can start to build a moral theory. Apart from the fact that your behavior would seem illogical were you to just give up your neighbors after hiding them, my guess is that most of us would agree—intuitively—that lying to the Nazi’s to protect your Jewish neighbors is also themoralthing to do.

但最终，这并不是对直觉的哲学运用的辩护。我还可以想出很多其他的思想实验，在这些实验中，我们的道德直觉无法就什么是正确的事情，提供清晰且容易达成一致的答案。而且，就像缸中脑的例子一样，道德直觉上的分歧通常源于先前理论承诺上的分歧。So, intuition can’tsupport那些理论上的承诺，只能让它们浮出水面。

If that’s the case, what does that say about the entire enterprise of moral philosophy? Is there a way to develop moral theories that does not depend on intuition? Or is there a way to rescue the use of intuition in philosophy from the problems I’ve raised here?

请收听本周的节目，“直觉是真理的指南吗?”，并在下方告诉我们你的想法!

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