Occasional Tales

Green and red. Can something be red and green at the same time? I assume that this means the thing can simultaneously red and green without these being discrete colours or some wavelength in the visible spectrum which stands halfway between them ( somewhere between orange and yellow ). As far as colours are concerned, such a thing isn’t possible, although I can imagine some state in which the colours shimmer a bit like an animated blend function in a graphics program. According to the book, there are things which can be in two complementary states simultaneously such as negative numbers which, when multiplied together, produce a positive number, but which can have square roots. Unfortunately, I think Cohen has misunderstood i. Also, I don’t think this is necessarily an example of something being X and not X simultaneously. I’m not sure. If anything, specific opinions may contradict our general outlook. Think of Dave “Lost my bike again” Cameron. He’s a Tory, but I believe he’s very pro...

First define your raven. Today's problem is about claiming all x are y and proving the assertion to be so. The declaration is that "All ravens are black". The philosopher gets out of trying to prove the claim by defining ravens as black and essentially denying any black bird of the corvida species is a raven. As someone points out, what happens if the raven catches a disease which turns it green temporarily? Is it still a raven during that time? I guess there are two problems. One is how to prove that all instance of x are y whether they're dead, alive, or yet to come; the other is a matter of definition, because if something ceases, at least for a time, to satisfy a definition, does it cease to be that thing? Oh, ah. According to the discussion, we're into the world of a priori vs. a posteriori which (and I hate these terms, to be honest, and understand them vaguely at best) are basically behind the whole rationalist vs. empiricist debate. I suppose with t...