Galileo and Einstein

Galileo's troubles with the Catholic Church which led to his house imprisonment were caused by a book advocating (under the thinnest disguise) the Copernican view that it is the earth's rotation which causes the apparent motion of the sun in the sky and the stars in the heavens. One of the chief arguments against the earth's rotation is that we see no direct effects. To this Galileo replies through his mouthpiece Salviati as follows.

SALVIATI … Shut yourself up with some friend in the main cabin below deck on some large ship, and have with you there some flies, butterflies and small flying animals. Have a large bowl of water with some fish in it; hang up a bottle that empties drop by drop into a wide vessel beneath it. With the ship standing still, observe carefully how the little animals fly with equal speed to all sides of the cabin. The fish swim indifferently in all directions; the drops fall into the vessel beneath; and, in throwing something to your friend, you need throw it no more strongly in one direction than another, the distances being equal; jumping with your feet together, you pass equal spaces in every direction. When you have observed all these things carefully (though there is no doubt that when the ship is standing still everything must happen in this way), have the ship proceed with any speed you like, so long as the motion is uniform and not fluctuating this way and that.