Everything in the cosmos is made of water
As a principle, the Greek challenged Thales to establish the Fundamental substance the Cosmos was made-up of. Thales of Miletus researched and concluded that all matter, regardless of its apparent properties, must be water in some stage of transformation. He interestingly noted that every landmass came to an end at the water's edge. The whole of earth must thus be floating on a bed of water from which it had emerged. When anything occurs to cause ripples or tremours in this water, he suggested that we experience them as earthquakes ! What is more crucial than this core research was the fact that he contributed to the development of 'scientific temperament' whilst the previous civilizations had relied only on incomplete religious scriptures to explain various phenomena around the world. For the uninitiated, Thales coached Anaximander, who in return coached Anaximenes the mentor of Pythagoras, the mathematician genius. It pains me to see water getting wasted...whatever, the reason. Thames, old man, came in handy.