" Originally everything had a name - a proper or peculiar name. Then the name became attached to a single element of the thing, and became applicable to all the other individual things that also contained that element: it is no longer a particular oak that is called tree, but anything that includes at least a trunk and branches. The name also became attached to a conspicuous circumstance: night came to designate, not the end of this particular day, but the period of darkness separating all sunsets from all dawns. Finally, it attached itself to analogies: everything was called a leaf that was as thin and flexible as the leaf of a tree. "
Foucault (via dranoparty