who was the first known scientist
Archimedes? (Edit): After a few seconds of googling, I found these names ... Thales, Aristotle, Anaximander (never heard of that last one!)
One might say the inventor of fire. Or the wheel.
There have been scientists since there have been people. That is what civilization is based on, engineering for buildings, agriculture for food. First famous scientists' accomplishments are based on work of countless others.
Who ever rubbed 2 sticks together and made fire from friction would be the first scientist.