I will just talk ab0ut words, but the ideas apply to concepts as well. It is very reasonbale to suppose that a typical word, such as 'apple', has a definite meaning. But then it can't be that all definitions are equally valid, since many will be inconsistent with the truth about what the word means, thus e.g. "'apple': a small glass or vessel for applying lotion to the eye." I guess the question 'how can definitions be rooted in reality and truth' then boils to the quesiton of what determines the meaning of a word. And that's one of the really big issues in the philosophies of language and mind. There are real issues about the extent to which words can be defined. People sometimes start out thinking that each word or concept has a definition in terms of conceptually necessary and sufficient conditions, on the model of "vixen': female fox". But in fact the vast majority of words seem not to have definitions like that: we just can't find ways of saying exactly what they mean. It...

I will just talk ab0ut words, but the ideas apply to concepts as well. It is very reasonbale to suppose that a typical word, such as 'apple', has a definite meaning. But then it can't be that all definitions are equally valid, since many will be inconsistent with the truth about what the word means, thus e.g. "'apple': a small glass or vessel for applying lotion to the eye." I guess the question 'how can definitions be rooted in reality and truth' then boils to the quesiton of what determines the meaning of a word. And that's one of the really big issues in the philosophies of language and mind. There are real issues about the extent to which words can be defined. People sometimes start out thinking that each word or concept has a definition in terms of conceptually necessary and sufficient conditions, on the model of "vixen': female fox". But in fact the vast majority of words seem not to have definitions like that: we just can't find ways of saying exactly what they mean. It...

Syntax has to do with grammarand semantics has to do with meaning. The syntax of a language can bethought of as a set of rules that determine which things are expressions of thelanguage and which things are not, and that determine the identity of eachexpression in the language. So, for example (oversimplifying in a numberof respects) the rules of English determine that 'dogs' is aparticular common noun in plural form and 'swim' is a particular verb in pluralform and that 'fish swim' is a sentence composed of those two. Notice that thesame sentence can take very different physical forms (‘FISH SWIM’). It can evenappear as a pattern of sound waves, when spoken. Notice also that I havejust told you about the syntax of the sentence without saying anything aboutwhat it means. Generalizing the idea: syntax is independent of semantics. Youcan think of the semantics of a language as a set of rules that determine whatall the expressions of the language mean - 'fish' means fish and 'swim' means ...

The word 'question' has several senses. In one sense it is a grammatical term referring to sentences of interrogative form. In another sense it is a semantic term, referring to the sort of thing that could be the content of an interrogative sentence - as in "The question that 'What is the meaning of life' is really asking". In the latter sense there can be sentences that have the form of a legitimate question yet nevertheless fail to pose legitimate questions - e.g. "Why has no dog ever barked?" or "Why have more people been to Berlin?". The answer to (3) is 'no', so the answer to (3) is 'no'.

The intuitions about the 'water' example that philosophers focus on are, as explained above, about reference. They are also about truth. It takes a little work to connect reference and truth to meaning. One line of thought goes as follows. Suppose that Oscar lands on Twin Earth. Both Oscar and Twin Oscar point to a sample of XYZ and say 'That is water'. What Twin Oscar says is true - he is speaking Twin English and Twin English speakers standardly call XYZ 'water'. But what Oscar says is false. He thinks that the stuff in front of him is water, the same kind of stuff he was familiar with on Earth. And that is the thought he is expressing when he says 'that's water'. But if what Twin Oscar says is true and what Oscar says is false, then their words must mean something different. I concur with Deniz that non-philosophers often don't respond to the example in the way that many philosophers do - although as yet no seroious data on this have been gathered. Often they either don't share the...