SEVENTEENTH AND EIGHTEENTH CENTURIES 119 



have seemed by no means unattractive at a time when the foremost natural 

 philosophers were at the same time pious Christians and subservient each 

 to his own Church. This even Galileo had been, as also those two of his 

 successors who have contributed more than any others towards giving natural 

 research its modern character — Boyle and Newton. These two are all the 

 more worthy of mention here as through their activities they have, each in 

 his own way, powerfully, if only indirectly, affected the development of 

 biology. 



Robert Boyle (1617-91) is generally looked upon as the first modern 

 chemist, in so far as he definitely broke away from the mystical speculations 

 of alchemy and made the object of chemistry the breaking up of complex 

 substances into their simplest elements. Thus he freed experimental effort 

 from the fantastic and semi-magical aims and means of the Middle Ages and 

 created a natural-scientific method based on rational calculations. On the 

 other hand, he had little bent for purely speculative problems and accepted 

 the general cosmic viev/s of the Church without reserve. 



Far more renowned and of far greater influence on the intellectual prog- 

 ress of man was Isaac Newton, one of the greatest pioneers of natural science 

 that the world has seen. Born in 1641, of a peasant family, he studied in 

 Cambridge, was for many years professor there, became in his old age Direc- 

 tor of the Royal Mint in London, and died at the age of eighty-four, honoured 

 and respected as few scientists have been. He was known everywhere for his 

 liberal-minded political views, deep religious sense, and modest, lovable 

 nature. 



The gravitation theory 

 Newton's important discoveries in the sphere of mathematics and optics are 

 universally known. Most famous and most vital from the point of view of 

 cultural development is, however, his theory of gravitation. Galileo had, it 

 will be remembered, established the fact that the movement of bodies on our 

 earth takes place on fixed, mathematically calculable principles. Newton 

 now proves that the same laws governing the movement of bodies at the 

 earth's surface also govern the movement of the heavenly bodies in their 

 relation to one another. All the world knows the story of how in his youth, 

 at the sight of a falling apple, he began to ponder the question whether it was 

 possible to calculate the movement of the moon round the earth according to 

 the same law of attraction as that governing the fall of the apple. He spent 

 twenty years working out his idea and finally laid down the well-known 

 principle that bodies attract one another with a force directly proportional 

 to the mass and in inverse ratio to the square of the distance. The extraor- 

 dinary importance of this discovery was by no means immediately clear to 

 everyone; it was at variance with the speculations of the Cartesian philoso- 

 phers as well as with the doctrines of the theologians, and it was not until 



