"Then, I said, let us begin and create in idea a State; and yet the true creator is necessity, who is the mother of our invention." - The Republic, Book II.
This has been abbreviated to the well worn saying "necessity is the mother of invention". I like what the internet has to say about this: "The author of this proverbial saying isn't known. It is sometimes ascribed to Plato, although no version of it can be found in his works." Another site gets it righter. Of course Plato may not have been the author, but rather repeating what had already been a common cliche. The context is one describing the entrepreneurial spirit and specialization and speculating that this is what brought about the design of a city state type civilization. A similar spirit is reflected in the writings of Adam Smith. I can't help but note the modern intellectualoid description of the same, which typically does away with the need for a creator or invention. Instead, everything simply