Leonardo Da Vinci, an artist, scientist, inventor, mathematician, engineer, and architect, was among the first great thinkers to apply the scientific method to his philosophies. He performed detailed experiments, in particular on the nature of frictional forces, from which he made observations and followed up by making theories which lead to new experiments. His work at the end of the 1400's preceded that of Newton by nearly 200 years.

Leonardo DiVinci Click for a self-portrait of Leonardo