Scientific achievements seem evanescent, because the very progress of science causes their supersedure; yet some of them are of so fundamental a natu… - George Sarton

It is childish to assume that science began in Greece; the Greek "miracle" was prepared by millenia of work in Egypt, Mesopotamia and possibly in other regions. Greek science was less an invention than a revival.

There are two kinds of people in the world, whom we might dub the jobholders and the enthusiasts. ...The majority of the kings and emperors were jobholders and so were many of the popes. ...Most of the creators in the field of art and religion, and many of them in the field of science, were enthusiasts. Now economic conditions may deeply affect the jobs and the jobholders, but they make little impression on the enthusiasts. ...the jobholders ...keep things going with enough continuity and smoothness; they are the builders of usages and customs, the defenders of morality and justice. ...the enthusiasts ...are the main instruments of change and progress; they are the real creators and troublemakers. The enthusiasts are the salt of the earth, but man cannot live by salt alone.

Men of science have made abundant mistakes of every kind; their knowledge has improved only because of their gradual abandonment of ancient errors, poor approximations, and premature conclusions.