**Formal Logic**

**The different kinds of logic**

The types of mysticism mentioned in the previous section are the kinds of non-conceptual understanding we have. We have basically four kinds of conceptual understanding: perceptual (based on perceptions or images of stored perceptions) and esthetic (based on emotions), and then the rather peculiar forms of humor and evaluation; and each of these involves different kinds of reasoning or logic (ways of combining expressions of understood facts so that new judgments result).

I think I will take up different kinds of reasoning based on perceptual concepts first, and treat esthetic understanding and its logic next, then give a brief look at humor, and leave evaluation until last, to round out this part of the book. And what I plan to treat in perception-based reasoning is first of all the logic of statements of fact, called "formal logic," then the logic of relations and the related, or the philosophy of mathematics, and finally the logic of science, in which I will discuss why scientific method is what it is, and in the process talk about the apparently anomalous logic of induction.

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