Aristotle
Greek philosopher and a scientist.
Let us then enunciate the functions of a state and we shall easily elicit what we want: First there must be food; secondly, arts, for life requires many instruments; thirdly, there must be arms, for the members of a community have need of them, and in their own hands, too, in order to maintain authority both against disobedient subjects and against external assailants....
For pleasure is a state of soul, and to each man that which he is said to be a lover of is pleasant.... Now for most men their pleasures are in conflict with one another because these are not by nature pleasant, but the lovers of what is noble find pleasant the things that are by nature pleasant; and virtuous actions are such... Happiness then is the best, noblest, and most pleasant thing in the world, and these attributes are not severed as in the inscription at Delos: Most noble is that which is justest, and best is health; but pleasantest is it to win what we love.
I do not agree with Plato, but if anything could make me do so, it would be Aristotle's arguments against him.