ABSTRACT
Galileo’s experiment, in which he purportedly dropped cannonballs and lighter objects from the leaning tower of Pisa, will always occupy a special place in the hearts of scientists. The results deduced from it were key components of Isaac Newton’s law of gravity in the seventeenth century and of Albert Einstein’s general theory of relativity. The profound importance of gravitational democracy of course still stood out like a rock in the sea of ideas. But then a different principle of democracy started to emerge above the waves of Einstein’s subconsciousness. Einstein concluded that they are related and he codified this in his celebrated principle of equivalence. The power of Einstein’s ‘naive’ approach is the way that he interwove time and gravity, concepts which had previously been regarded as totally independent, as he struggled to develop the insights he would need to formulate the general theory of relativity and gravity.
