Substance The term “substance” has two main uses in philosophy. Both originate in what is arguably the most influential work of philosophy ever written, Aristotle’s Categories. In its first sense, “substance” refers to those things that are object-like, rather that property-like. For example, an elephant is a substance in this sense, whereas the height or colour of the elephant is not. In its second sense,

Introspection Introspection is the process by which someone comes to form beliefs about her own mental states. We might form the belief that someone else is happy on the basis of perception – for example, by perceiving her behavior. But a person typically does not have to observe her own behavior in order to determine whether she is happy. Rather, one makes this determination by

Rudolph Hermann Lotze (1817–1881) Hermann Lotze was a key figure in the philosophy of the second half of the nineteenth century, influencing practically all the leading philosophical schools of the late nineteenth and the coming twentieth century, including (i) the neo-Kantians; (ii) Brentano and his school; (iii) The British idealists; (iv) William James’s pragmatism; (v) Husserl’s phenomenology; (vi) Dilthey’s philosophy of life; (vii) Frege’s new

Mathematical Structuralism The theme of mathematical structuralism is that what matters to a mathematical theory is not the internal nature of its objects, such as its numbers, functions, sets, or points, but how those objects relate to each other. In a sense, the thesis is that mathematical objects (if there are such objects) simply have no intrinsic nature. The structuralist theme grew most notably from

Socrates (469—399 B.C.E.) Socrates is one of the few individuals whom one could say has so-shaped the cultural and intellectual development of the world that, without him, history would be profoundly different. He is best known for his association with the Socratic method of question and answer, his claim that he was ignorant (or aware of his own absence of knowledge), and his claim that the