The value of introspection

Even if language was a finite construct, would corpus methodology still be the best method of studying language? Why bother waiting for the sentences of a language to enumerate themselves, when by the process of introspection we can delve into our own minds and examine our own linguistic competence? At times intuition can save us time in searching a corpus.

Without recourse to introspective judgements, how can ungrammatical utterances be distinguished from ones that simply haven't occurred yet? If our finite corpus does not contain the sentence:

*He shines Tony books

how do we conclude that it is ungrammatical? Indeed, there may be persuasive evidence in the corpus to suggest that it is grammatical if we see sentences such as:

He gives Tony books
He lends Tony books
He owes Tony books

Introspection seems a useful and good tool for cases such as this. But early corpus linguistics denied its use.

Also, ambiguous structures can only be identified and resolved with some degree of introspective judgement. An observation of physical form only seems inadequate. Consider the sentences:

Tony and Fido sat down - he read a book of recipes.
Tony and Fido sat down - he ate a can of dog food.

It is only with introspection that this pair of ambiguous sentences can be resolved e.g. we know that Fido is the name of a dog and it was therefore Fido who ate the dog food, and Tony who read the book.