No language of thought

Another possibility is that there is no language of thought (LOT) at all. Maybe we just use our ordinary languages to think; if we don’t have language, we can’t think very well.

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Maybe early humans didn’t really have a language of thought. They probably couldn’t think as well as we can because they lacked this tool.

So maybe early humans were just a bit cleverer than other animals. They made noises to try to communicate — just like other animals do — and slowly developed a sophisticated language ability. They also started using their language to think and this helped them to develop mentally.

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Perhaps we became cleverer because we used tools, like language.

By this view, language is just one of the tools that humans used in order to develop advanced mental capacities.

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Humans are clever because our use of tools made it easier to think at a higher and higher level. Language is a very important tool — but still just one of many tools.