In my blog two weeks ago I wrote about an investigation by the Lithuanian philosopher Vilius Dranseika. In this investigation Dranseika tested a philosophical intuition on memory. Philosophical intuitions are often subject of investigation in experimental philosophy, but what are actually philosophical intuitions? To make matters short, I want to define them here as immediately justified beliefs. However, philosophical intuitions are not “just” beliefs in the sense that a philosopher who has a certain intuition thinks: It’s what I think, but maybe I am wrong and maybe matters are different. No, a philosopher who has a philosophical intuition thinks that it is true and that every reasonable person will agree that this intuition is true. Seen this way, we can define a philosophical intuition more precisely as an immediately justified true belief. Moreover, intuitions are not only true, but, as said, they are immediately true. Of course, not everybody will an intuition proposed by a philosopher immediately consider true. Then the philosopher will not say: “Maybe I am wrong and maybe the intuition is not as intuitively true as I thought.” No, s/he’ll find reasons to explain why the intuition nevertheless is true, for philosophers are good in confabulating reasons, for it is their job. And in the end she can always “play the man” and say: “Strange that you don’t see it. Everybody sees so.” Actually, it’s the last rescue in case you cannot convince your opponent, for it’s typical for an intuition that you cannot give it a factual foundation. Intuitions are simply true. Are they?
Before I want to discuss this question, I want to distinguish philosophical intuitions yet from psychological intuitions. Rather than being a form of true knowledge, psychological intuitions are a kind of “gut feelings”, and basically they are open to refutation. “Intuitively, I think that this man is a scoundrel” (but maybe he is the most honest man in the world). “Intuitively I think we should go to the left” (but maybe it was the road to the right that let to our destination). Etc.
Now I go to the question whether philosophical intuitions are true. As a first step to undermine the idea they evidently are, I want to discuss an example from psychology: The well-known Müller-Lyer Illusion. Please, click here for a picture of the illusion. Most people believe that the line on the top is shorter than the line under. Nonetheless both lines have the same length. (Measure them if you don’t believe!) Your intuitive belief is contrary to the fact. However, the Müller-Lyer figure is an illusion, so an observation error. It’s not a (false) philosophical intuition. But if such an apparently true observation about the lines in the Müller-Lyer Illusion can be false, why not then the same so for apparently true illusions? And that’s what I want to maintain here: Most philosophical illusions are false or not true to that extent as philosophers thinks. With the latter I mean that their truth is limited to certain contexts, like the context of investigation, culture, and the like (and even then I have my doubts).
There are so many intuitions in philosophy that it’s simply impossible to discuss them all, certainly in a blog like this one. It’s even impossible to discuss a representative fraction of the existing philosophical intuitions. However, they are especially used in thought experiments and therefore, by way of illustration of my critique, I want to discuss a much-used thought experiment in the discussion about personal identity in analytical philosophy: brain swapping. Such thought experiments have the form that the brain of person A is transplanted to the body of person B. Variations of this standard case are that the brains of A and B are switched; that the halves of A’s brain are transplanted into different bodies; that only the information of A’s brain is brought to B’s brain (after that first the information of B’s brain has been removed); or even that persons are copied and are “teletransported” to another place. (see here) Of course, everybody is free to invent what s/he likes, but can this thought experiment be the basis of a serious philosophical discussion? For the idea of brain swapping in one form or another is based on the implicit assumption that brain swapping is possible and that with swapping brains we swap personalities. Weren’t it so, it would have no sense to draw conclusions from such thought experiments about the characteristics of our personal identity. Nonsense will lead only to other nonsense. And that’s what is the case here. I don’t mean that the ideas about personal identity are nonsense, but if they are correct it is not because of these thought experiments. Take for example the idea that we swap personalities if we swap brains. It is founded on the intuitive idea that we are our brains. But if I formulate it this way, many philosophers will say: Of course, we are not our brains, we are more. I guess, that even some of those philosophers who use brain swap thought experiments in their discussions on personal identity will deny that we are our brains. Why then do they use such brain swap arguments in order to substantiate their views? I’ll give one example why your identity is not just in your brain. Simply said, some runners have fast-twitch muscles and others have slow-twitch muscles. Fast-twitch muscles will never make you a good long-distance runner, while slow-twitch muscles will never make you a good sprinter. Isn’t it not so then that the type of muscles a runner has is a part of his or her personal identity?
The upshot is: Philosophical intuitions are just opinions. Another thing is, of course, whether we do without them.
Elijah Chudnoff, Intuition. Oxford: Oxford University Press, 2013.