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it. He published his celebrated laws, which are known as Kepler's 

 laws, from which, in later times. Sir Isaac Newton deduced by mathe- 

 matical demonstration the celebrated law of gravitation. It is extremely 

 interesting to us who look back upon these discoveries with the re- 

 flected light which Newton's genius has thrown upon them, to read 

 Kepler's writings, and see in what manner this remarkable man re- 

 garded his own discoveries. Kepler was a scholar as well as a mathe- 

 matician ; and he was a profound student of the Timmis of Plato, and 

 was charmed with that beautiful fiction in which Plato imagines the 

 cosmogony of the world, and describes the Demiurgus persuading 

 Chaos to become Cosmos ; and ends by the assertion, bold for his age, 

 considering that it was in opposition to the heathen mythology of the 

 times, that the sun was an animal, the earth an animal, the moon an 

 animal ; that the gods, as Venus, Diana, and Mercury, were deities 

 who were subordinate to these great beings. Kepler was caught with 

 the beauty of this Platonic fiction. He imagines the earth swimming 

 in her orbit round the sun as an animal with intelligence. He discusses 

 in his book, Harnionices Mtmdi, the possibility of the earth seeing with- 

 out eyes, and hearing without ears ; and arrives at the conclusion that 

 the earth must be an animal, for three reasons. First, the earth moves 

 uniformly on her axis, and none but an intelligent being could know 

 how to keep uniformly moving without going faster at one time than at 

 another. Secondly, he says, the earth, as he has proved by his laws, 

 describes a particular path round the sun and no other, and moves with 

 a particular velocity at each portion of that path ; and this, he says, 

 the earth can only do by observing the angles made by the heavenly 

 bodies, calculating its position — going slowly when it had to go slowly, 

 and fast when it had to go fast — by observing the planetary angles. 

 Lastly, he says, the earth must be an intelligent animal, for the highest 

 and best of all reasons, which he also learned from Plato — because the 

 earth is a great geometer. The earth, he says, produces within her 

 bosom crystals such as these which are before you, which are related to 

 certain forms shown in the diagram — Euclidean solids capable of being 

 inscribed in spheres. No creature, says Kepler, could know the mys- 

 terious properties of the solids inscribed in spheres, excepting an intel- 

 ligent geometer. The earth produces crystals and forms closely related 

 to these in her own bosom, and therefore by the maxim de opifice 

 testattir opus (which we may translate by *' the carpenter is known by 

 his chips"), we come to the conclusion that the earth must be a geome- 

 ter, for she produces perfect geometrical forms. Kepler goes further, 

 and proceeds to discuss the question what sort of an animal is this earth ? 

 He says the earth is no lively animal like a lap-dog, ready to obey your 

 nod ; she is a sluggish, lazy, intelligent creature, like an ox, or perhaps, 

 I should say, like an elephant. Now, a very remarkable fact bearing 



