I am not a philosopher of art, so I will defer to another panel member who is, but I do remember once visiting a museum in New York City that had an exhibit titled "The Baker's Art", consisting of elegantly decorated cakes and breads.

The land mass that we call "Kansas" would still exist (unless, of course, the reason that everyone died was that the entire Earth blew up, or something like that). But Kansas the state is a "socially constructed" object (of the sort discussed by John Searle in his book The Construction of Social Reality ) and would thus no longer exist. On the other hand, there might still be books and maps that refer to that land area as "Kansas", so extraterrestrials visiting Earth later on (or Earth animals that evolve to replace humans as intelligent residents of a future Earth) might be able to refer to it that way. Most artifacts are like this: The substance they are made of is human- or mind-independent; the use made of them is not---so, a flat tree stump would still be a flat tree stump after all humans die, but if it had been used as a table by some human, it would no longer be a table.

I agree with Jonathan Westphal that there's no simple answer to your question as you pose it. One (no doubt overly simpleminded) way to approach an answer to the question is to make a list of things that exist and then see if they have any properties in common. But what would you put on this list? You could think of beginning with a list of all of the kinds of individual things that exist: There are people, there are plants, there are animals, etc. That's going to be a pretty long list, but do these kinds of things really exist? Or is it better to say that only individual things of these kinds exist? So, instead, you should list all the individual people (Adam, Eve, Cain, Abel, ..., you, me), list all the plants (the rose on my desk, the rose on your desk, etc.), list all the animals (my pet cat Bella, your pet dog Fido, etc.). That's going to be an even longer list. But are there such things? Consider any physical object. We know from physics that it's not really a single...

It depends on what you want to do with your knowledge of mereology. The Department of Philosophy at the University at Buffalo (State University of New York) is a world center for research on applications of ontology to artificial intelligence and informatics, and much of their work is based on various theories of mereology. For further information, link to "Areas of Study: Ph.D. with a focus in Ontology" (where you'll also see an old photo of me if you scroll down the page :-) That page also has links to the National Center for Ontological Research.

It's not so much that some logicians believe that there are no contradictions as it is that there are different ways of dealing with them. There are different kinds of paraconsistent logics. Many (e.g., "relevance logics") got their start by trying to handle the so-called paradoxes of the material conditional (e.g., that from a contradiction, anything can be derived). There are also situations in which it makes sense to allow for propositions that can be both true and false as well as propositions that are neither true nor false, in addition to ones that are either true or else false (see Belnap's paper, cited below). (Just for a quick example: "This sentence is false" might be both true and false, whereas "Colorless green ideas sleep furiously" might be neither true nor false.) In artificial intelligence, there have been applications of relevance logics to deductive knowledge bases (see the Martins & Shapiro paper, cited below): Suppose you have a deductive knowledge base and that person A...

I would like to focus on your last question: Is it possible that plants and animals have thoughts just like people? Let's take animals first. We are animals, so at least some animals have thoughts just like people. Our nearest animal relatives--the primates--probably have thoughts very much like ours, though (perhaps with a few very special exceptions) theirs differ from ours in that none of theirs are expressed in language (while some, if not all, of ours probably are). (The few very special exceptions would be those primates who have been taught various kinds of sign languages or artificial languages.) Going down the evolutionary tree, I'd be willing to say that other mammals have thoughts not unlike ours, etc. In fact, I'd be willing to say that any animal that has a suitably rich nervous system might have thoughts not unlike ours (what counts as "suitably rich" is open for debate, of course). In fact, I'll propose that having a nervous system (either biological or artificial) is a necessary...

Both 'tri' and 'drei' mean "3", and both 'angle' and 'eck' mean, well, "angle", so on that basis, one can argue that your English and German words "mean the same". They also surely refer to the same geometrical objects, so on that basis they also "mean the same". On the other hand, it's not at all clear that any two expressions, even in the same language, "mean the same". There are usually subtle differences between them. Take for instance 'lawyer' and 'attorney'. Probably most native English speakers use these words as more or less synonymous, though they have clearly different etymologies and once had somewhat different shades of meaning that have largely, if not entirely, been lost. Their "distribution" in the language also differs: There are times one says 'lawyer' and times one says 'attorney', even though one would be hard put to explain why. But those differences might be enough to indicate a difference in meaning. Getting back to 'triangle' and 'Dreieck', however, there's another...

Here's one quick answer to your first question: What makes a bottle a bottle (more precisely: what makes something a bottle) is whether someone uses it as a bottle, not what it's made of or what its form is. Although the rest of your question is stated in Aristotelian and mediaeval terms of substance and accident, I think that part of your question concerns the nature of artifacts. On that topic, you might take a look at my colleague Randall R. Dipert's Artifacts, Art Works, and Agency (Temple University Press, 1993).

First, take a look at Question 2384 and its answers, which are closely related to your question. Your question is related to what is called the "inverted spectrum", a philosophical puzzle posed by John Locke, one version of which is this: Is it possible that objects that have the color you describe as "red" are seen by me as if they had the color you describe as "green", even though I also describe them as red, and vice versa? Posing the problem is difficult; e.g., objects arguably don't "have" colors, but reflect light of certain wavelengths, which are perceived by us as certain colors. "Is the color that I perceive as, and call, red the same as the color that you perceive as what I call blue?" is another way of posing the puzzle. Part of the problem is that there doesn't seem to be any way to decide what the answer is (if, indeed, it has an answer). What experiment would decide between these? Perhaps such color-perceptions (more generally, what are called "qualia") are such that a...

Some terms that are used for what I think you have in mind are "informal logic" and "critical thinking". To see if those are, indeed, what you have in mind, you might check out the article on Informal Logic in the Stanford Encyclopedia of Philosophy. And there's some discussion of "critical thinking" in SEP in its article on Philosophy for Children (but the topic of critical thinking is by no means limited to children!).