"Necessity, the mother of invention"

I think that "necessity, the mother of invention" means that it's what we need that makes us come up with all these inventions. like wheel chairs, we need wheel chairs for our elders so we made them. Another thing we made was a car, we needed a better way of transportation so we made one, and the same rules apply for making medicine. The term"mother of invention" does not mean that there is literally a mother of invention but that necessity is the mother of inventions, and necessity is what we need to live, so we invent.
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