At first he who invented any art that went beyond the common perceptions of man was naturally admired by men, not only because there was something useful in the inventions, but because he was thought wise and superior to the rest. But as more arts were invented, and some were directed to the necessities of life, others to its recreation, the inventors of the latter were always regarded as wiser than the inventors of the former, because their branches of knowledge did not aim at utility.
For the real difference between humans and other animals is that humans alone have perception of good and evil, just and unjust, etc. It is the sharing of a common view in these matters that makes a household and a state.
You'll understand what life is if you think about the act of dying. When I die, how will I be different from the way I am right now? In the first moments after death, my body will be scarcely different in physical terms than it was in the last seconds of life, but I will no longer move, no longer sense, nor speak, nor feel, nor care. It's these things that are life. At that moment, the psyche takes flight in the last breath.
Governments which have a regard to the common interest are constituted in accordance with strict principles of justice, and are therefore true forms; but those which regard only the interest of the rulers are all defective and perverted forms, for they are despotic, whereas a state is a community of freemen.
A sense is what has the power of receiving into itself the sensible forms of things without the matter, in the way in which a piece of wax takes on the impress of a signet-ring without the iron or gold.
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.