To modern educated people, it seems obvious that matters of fact are to be ascer\xadtained by observation, not by consulting ancient authorities. But this is an entirely modern conception, which hardly existed before the seventeenth century. Aristotle maintained that women have fewer teeth than men; although he was twice married, it never occurred to him to verify this statement by examining his wives' mouths.
Some things are believed because people feel as if they must be true, and in such cases an immense weight of evi\xaddence is necessary to dispel the belief.
It is not by prayer and humility that you cause things to go as you wish, but by acquiring a knowledge of natural laws.
Science, ever since the time of the Arabs, has had two functions: (1) to enable us to know things, and (2) to enable us to do things.
The modern power of the State began in the late fifteenth century and began as a result of gunpowder. From that day to this, the authority of States has increased, and throughout it has been mainly improvement in weapons of war that has made the increase possible. This development was begun by Henry VII, Louis XI, and Ferdinand and Isabella. It was artillery that enabled them to succeed.