Language is defined by a set of symbols and meanings.
It's not the end of discussion by a long shot. It's a cheap way to make it seem like he's right, however as it's already been explained there are more than just spoken or written languages.
are you changing your original definition just so you can keep arguing?
If I flicked you off, would you understand what it was? That's language. If I did this would you understand? That's language.
Language doesn't have to be words or anything like that, free your mind.
If you flicked me off and I didn't understand the concept of the middle finger (something that incidentally evolved way after the creation of spoken language) I doubt I'd care
anyway, the original discussion was can someone think without language so I'll stick to that and I'll stick to what I said. It looks like you're arguing I'm wrong now because I guess you think body/other forms of non-verbal language mean that even if you're not using a verbal form of language some form is being used every time you think. Which assumes what...? if you flick me off yes, that's a form of language but it's presupposed by a thought which doesn't necessarily have to involve language.
picture through some amazing twist of nature that we had evolved without bodies just as giant brains. there'd be no possible way for us to communicate and it looks like you're trying to say that because we wouldn't be able to communicate (through body language, dance, what have you) we wouldn't be able to think. I don't buy that.