NATURAL PHILOSOPHY SWANN 235 



ing notions of the day there should be seven planetary bodies and no 

 more — the earth, moon, Mercury, Venus, Mars, Jupiter, and Saturn. 

 Hear the argument of Francesco Sizzi, himself a Florentine 

 astronomer, against this assertion of Galileo : ^ 



There are 7 windows in the head — 2 nostrils, 2 eyes, 2 ears, and a mouth ; 

 so in the heavens there are 2 favorable stars, 2 unpropitious, 2 luminaries, 

 and Mercury alone undoei<led and indifferent. From which and many other 

 similar phenomena of nature, such as the seven metals, etc., which it were 

 tedious to enumerate, we gather that the number of planets is necessarily 7. 



Moreover-, the satellites are invisible to the naked eye, and therefore can 

 have no influence on the earth, and therefore are useless, and therefore do 

 not exist. 



Besides, the Jews and other ancient nations as well as modern Europeans 

 have adopted the division of the week into seven days and have named them 

 from the seven planets ; now, if we increase the number of planets this whole 

 system falls to the ground. 



You can judge of the wrath and indignation which Galileo brought 

 upon his head when he contended in reply that whatever might be 

 the force of these arguments as a reason for believing beforehand 

 that no more than seven planets would be discovered, they hardly 

 seemed of sufficient weight to destro}^ the new ones when seen. 



It was Galileo who wrested from nature the secret of the laws 

 which govern motion — the law^s which govern the motions of almost 

 everything, the planets in the heavens, the flywheel of the steam 

 engine, the bird in flight — yes; and in a large measure at any rate, 

 the motions of the innermost parts of the very atoms of matter 

 itself. But Galileo did not evolve these law^s out of the dogmas of 

 imagination but by the more humble and safe appeal to direct experi- 

 ment. He marked out the method of approach, the experimental 

 method, which has been the model for all succeeding generations 

 in their search for the fundamental facts which govern the workings 

 of nature. 



The laws of motion may be written on a post card, but their conse- 

 quences have not been exhausted in all the books men of science have 

 written in 300 years. As we all know, Galileo's life w^as beset with 

 tribulation. He lived in an age when there was little tolerance for 

 one who followed not the conventionalities of thought of the day. 

 To question the learning of the past was arrogance, to discover new 

 truth was blasphemy, and so he died, having sown, however, the 

 seeds of the fruit that was to come. He died in a world seething 

 with superstition and ruled by the dogmas of an ancient past, but a 

 world wdiich was destined only a year later to see the birth of one 

 who is rated by many as the greatest genius of all time, that great 

 prince of England's men of science, Isaac Newton. 



- Quoted from Sir Oliver Lodge's Pioneers of Science. 



