Day 6

Note that so far we've not really dealt with meaning. We've touched on it a little in syntax and morphology, but only as a rough shorthand (ideally, we wouldn't care about meaning at all at those levels).

Semantics is the layer of our onion that deals with meaning. Specifically, it deals with literal meaning and propositions. Semantics doesn't tend to get above the level of the sentence and can't really deal with non-literal meaning or conversations or implications.

So what's semantics for?

There's two main strains of semantics - formal semantics and cognitive semantics. Cognitive semantics cares about how meaning is processed in real live squishy brains.

Before we go on, we'll have to define a few terms - utterance, sentence and proposition. A proposition is the a thing that can be true or false. We can't exactly write down propositions directly (except when we start converting in to logical languages) as they're abstract meaning-things, but we can express them with the corresponding indicative sentences. (I will put propositions in square brackets, sentences in italics and utterances in double quote-marks) [john slept] is either true (if john is sleeping) or false (if he is not). This can turn up in lots of ways - John slept. is one and is an statement and Did John sleep? is a question but both contain the same propositional content. Finally, while sentences are idealised constructions, utterances are unique actual expressions. At 0:24, December 09 2011, I uttered "John slept." This becomes really important when dealing with words like he or that one.

So formal semantics mostly converts actual sentences into a logical, mathematical language and connects this to the syntax to form the link between structure and meaning. There's actually really cool stuff going on in there which should make you squee, but it probably won't yet, because it takes a bit of introducing.

A bit more accessible is cognitive semantics, which is a more interested in how we process meaning and link it to language. There's a particularly cool (to me) theory to make an example of this called prototype theory.

What is a bird? Describe one to me. Do birds fly? Do they have wings? Are they feathered? Are any of these necessary or sufficient for being a bird? What about penguins? What about bats?

Prototype theory says that all the things that could be a bird are judged by their relation to a prototype, a mental ideal of 'birdness'. Maybe a pigeon or a robin or a sparrow are prototypical birds for you. (Note - don't confuse this with actual, physical birds. Prototypes are mental; actual things which correspond to them are exemplars.) If it shares a lot of features with the prototype it's a 'good' bird. If it shares few, but does share a lot of features with 'good' birds, it might still be a bird.

Anyway, I've talked enough. Time to get just under the skin.