Seneca

“ VIII. What answer are we to make to the reflexion that pleasure belongs to good and bad men alike, and that bad men take as much delight in their shame as good men in noble things? This was why the ancients bade us lead the highest, not the most pleasant life, in order that pleasure might not be the guide but the companion of a right-thinking and honourable mind; for it is Nature whom we ought to make our guide: let our reason watch her, and be advised by her. ”

“ Let not his confidence be without knowledge, nor his knowledge without steadfastness: let him always abide by what he has once determined, and let there be no erasure in his doctrines. It will be understood, even though I append it not, that such a man will be tranquil and composed in his demeanour, high-minded and courteous in his actions. Let reason be encouraged by the senses to seek for the truth, and draw its first principles from thence: indeed it has no other base of operations or place from which to start in pursuit of truth: it must fall back upon itself. ”

“ Even the all-embracing universe and God who is its guide extends himself forth into outward things, and yet altogether returns from all sides back to himself. Let our mind do the same thing: when, following its bodily senses it has by means of them sent itself forth into the things of the outward world, let it remain still their master and its own. ”