i am leaning towards no.
for the bird example, when i am doing tasks i am not running a commentary in my head. "reach left hand out and pick up the fork. poke assparagus with the fork. hmm, i wonder if this is too big to fit in my mouth...." etc. even more complex tasks do not require a running commentary. i think that when i talk to myself..in my head, or out loud, it is a method of focusing my thoughts. but there my be other methods for that.
ok, so then i went to this question. and this may be complete ignorance and i may be wrong (and i mean no disrespect or offence). someone who is born deaf may have no concept of a spoken language. it would seem difficult to think in a language that has never been spoken. perhaps people that picture things in their heads will have ASL going on, i really don't know. but short of that, they would be thinking without talking to themselves.
edit - perhaps that should be ignored. i spoke to someone smarter than me, and it seems that my definition of language was too rigid. if you consider language in the broadest sense, which is applying symbles to concepts, then language is probably required for abstract and complex thought. i have trouble imagining how this will be done because i think verbally and do not form mental images.
Do we need language to think?
I had a small (and random) debate with a friend today on the beach on this subject. I am to torn to make a final decision on the matter.
I know that I always talk to myself in my head for any menial task and in chess. I cant think without an internal monolog. However, when a bird swoops down on some prey, is this a thought process or a reaction. Or is a reaction identical to thought just faster.
I definatly dont feel it would be possible for the great philosophers of the past and preasent to have addapted such complex ideas without language.
Such a daft question to have taken up my day!
What do others think?