We need language really to exchange thoughts in one head to another head, in a slightly richer manner than an ape can. To "think" we don't really need language

We need language really to exchange thoughts in one head to another head, in a slightly richer manner than an ape can. To "think" we don't really need language (the oral kind the non- deaf think they are thinking in). Sign language among the born deaf, if allowed to develop without a need to learn spoken languages of the non-deaf, would be clear evidence that thought underlies oral language. And words (that stuff produced for your ear) need not be the only way to think.