The world used to be full of magic and then science took it all away. If you went to university in the 16th century, you learned about a universe that pulsed with life and purpose. You learned that every individual thing has a natural motion to its proper end, an internal appetite for what is good for itself. A man, for example, desires to use his reason. An acorn has an appetite to turn into an oak. Even a stone thrown into the air, Aristotle wrote, has an appetite to fall to the ground.
The so-called scientific revolutionaries of the 17th century laughed at this view of nature. They said that it was an elaborate fantasy spun out of words rather than things, no more real than sprites. As Thomas Hobbes observed, it was pretty funny to say that ‘heavy bodies’ knew what was good for them (falling), when even human beings – who in England had just come through a civil war – did not seem to have a clue.