The things best to know are first principles and causes, but these things are perhaps the most difficult for men to grasp, for they are farthest removed from the senses.
The investigation of the truth is in one way hard, in another easy. An indication of this is found in the fact that no one is able to attain the truth adequately, while, on the other hand, no one fails entirely, but everyone says something true about the nature of all things, and while individually they contribute little or nothing to the truth, by the union of all a considerable amount is amassed.
Although it may be difficult in theory to know what is just and equal, the practical difficulty of inducing those to forbear who can, if they like, encroach, is far greater, for the weaker are always asking for equality and justice, but the stronger care for none of these things.
There is nothing grand or noble in having the use of a slave, in so far as he is a slave; or in issuing commands about necessary things. But it is an error to suppose that every sort of rule is despotic like that of a master over slaves, for there is as great a difference between the rule over freemen and the rule over slaves as there is between slavery by nature and freedom by nature . .
Some persons hold that, while it is proper for the lawgiver to encourage and exhort men to virtue on moral grounds, in the expectation that those who have had a virtuous moral upbringing will respond, yet he is bound to impose chastisement and penalties on the disobedient and ill-conditioned, and to banish the incorrigible out of the state altogether. For (they argue) although the virtuous man, who guides his life by moral ideals, will be obedient to reason, the base, whose desires are fixed on pleasure, must be chastised by pain, like a beast of burden.
True happiness comes from gaining insight and growing into your best possible self. Otherwise all you're having is immediate gratification pleasure, which is fleeting and doesn't grow you as a person.