If a bit of perceptual behavior is a trope, so is any response to a stimulus, and so is the stimulus, and so therefore, more generally, is every effect and its cause. When we say that the sunlight caused the blackening of the film we assert a connection between two tropes; when we say that Sunlight in general causes Blackening in general, we assert a corresponding relation between the corresponding universals. Causation is often said to relate events, and generally speaking (...) any event is a trope: a smile, a sneeze, a scream, an election, a cold snap, a storm, a lightning flash, a conspiracy, perhaps a wave, and so on up to such big and important events that they have proper names, like the Passover and Lulu the H-bomb explosion. We have called a trope a "case" of its universal, while the universal is the "kind" of the trope, so it is no surprise that a medical "case" is a trope--in the sense, at any rate, in which a person is said to have a case of typhoid fever rather than to be a case of it. A high-school boy, uncoached, has assured me, "Of course there's such a thing as Redness--this pencil has a case of it." When a scientist reports a temperature or a velocity or a viscosity he is reporting a trope--not a universal, because it is a once-for-all occurrence, but not a concrete thing either, though doubtless a component of one. He is likely to call it an "aspect" of the thing or, preferably, a "state," and generally speaking a "state" of a thing or a nation is a trope. Recent developments in sub-atomic physics, a none too reliable oracle, suggest that an electron, e.g., just is an existent state, and that the common-sense philosophy of concreta here abdicates altogether in favor of the trope. (shrink)