Human beings have Love for one another inborn in them - Love, reassembler of our ancient nature, who tries to make one out of two and to heal human nature.
Laws are partly formed for the sake of good men, in order to instruct them how they may live on friendly terms with one another, and partly for the sake of those who refuse to be instructed, whose spirit cannot be subdued, or softened, or hindered from plunging into evil.
The choice of souls was in most cases based on their own experience of a previous life... Knowledge easily acquired is that which the enduing self had in an earlier life, so that it flows back easily.
True opinions are a fine thing and do all sorts of good so long as they stay in their place; but they will not stay long. They run away from a man's mind, so they are not worth much until you tether them by working out the reason. Once they are tied down, they become knowledge, and are stable.