I have heard philosophers propose that thought is dependent upon language: that without language one cannot have thoughts, that we can think of thoughts as sentences, etc. There seems to be a strong correlation, in many philosophers' writings, between thoughts and sentences of a language. In some limited sense, this makes sense to me. Creatures that clearly do not have language (platypuses, say) do not seem to have thoughts; whatever goes through their heads, they do not seem to do what we do when we think. And for those of us who do have language skills, thoughts take the form of sentences in whatever language(s) we speak.
But philosophers often assume that thoughts just ARE those sentences, that it is nonsensical even to say that "thoughts take the form of sentences in a language". But how can the ability to think depend on the possession of language skills? If a human baby were never taught to speak or to understand a language, and thus arrived at the age of 30 with no language skills, would we really want to say that he had never had a thought in his life? What if he had survived half that time on a deserted island through ingenuity and invention?
Unfortunately, children are occasionally neglected to the point where they do not acquire language skills. (And even more unfortunately, scientists call these children "feral".) It strikes me as inaccurate to say that it is impossible for these children, despite their stunted development, to have a single thought. Do any philosophers have similar intuitions? And if so, is the ability to think linked to, perhaps, membership in a species that is capable of developing language? Are any philosophers less homo-centric and inclined to allow that chimpanzees or other animals are capable of extremely rudimentary thoughts?