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Aquinas says the intellect is never deceived about what a thing is, only in judging. What does that mean?

Ikechukwu Anyanwu Fellow
· 3 replies
TruthMedieval ChristianScholasticismAristotle#aquinas#error#falsity#intellect
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Its coordinates: 2.5 Truth

My senior students are reading a little of the Summa with me, and one passage stopped us. In the first part, where Aquinas asks whether falsity is in the intellect (question 17), he says something like this, following Aristotle: just as the sense is not deceived about its proper object (the eye about colour), so the intellect is not deceived about its proper object, which is what a thing is. Falsity arises when the intellect joins or separates, that is, when it judges that something is or is not so.

My students found this outrageous on a day when we had been discussing sceptics. "So Aquinas thinks we can't be wrong about what things are? People have been wrong about what the sun is for thousands of years!"

I tried to explain that grasping what a thing is is not the same as a theory about it, but I am not sure I explained it well. Can someone help me put it simply?

  • What exactly does Aquinas say cannot be false, and why?
  • How does this answer, or fail to answer, the sceptic who says we might be wrong about everything?

At our school we also talk about chi and destiny, and the boys asked whether a person's chi can be mistaken about what he is. That may be a different thread.

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3 answers

  1. Aoife Kilbride

    Fellow

    Here's how my lecturer put it. The intellect has two operations. The first, simple apprehension, is just grasping a nature: understanding what "sun" is meant to pick out, without saying anything about it. The second, judgement, joins or separates: "the sun goes round the earth". Only the second can be true or false, because only it makes a claim.

    So Aquinas is not saying people can't be wrong about the sun. They were wrong in a judgement. What he says can't be false is the bare grasping, in the way a word on its own isn't false.

  2. Meera Kulkarni

    Fellow

    There is a close parallel in Indian logic. Nyāya distinguishes non-conceptual perception, which simply takes in an object, from conceptual perception, which grasps it as something: as a pot, as blue. Error belongs to the second. In the stock example of mother-of-pearl seen as silver, the first contact with the shining thing is not where the mistake lies; the mistake is in taking it as silver.

    Both traditions locate error in the moment of taking as. The sceptic's question is whether anything we care about lies before that moment.

  3. Ikechukwu Anyanwu

    Fellow

    Aoife, "a word on its own isn't false" is the line I needed for the boys. Meera, the mother-of-pearl example is perfect, and they'll enjoy hearing that a Nyāya logician and Aquinas put the mistake in the same place, centuries and continents apart.