FOR EVER AND EVER 



From our limited experience we conclude that eggs and hens alternated for many, 

 many years before we arrived, and that they will continue to alternate long after wc 

 are gone. Looking forward we see world without end; looking backward we see 

 world without beginning. That illustrates about all we mean by always, and about 

 all we know of natural law 



perhaps, and there burns up and eventually returns to the atmosphere, having 

 furnished energy for the happy thought of a poet. All our knowledge, all our 

 certainties, come in fact from our experience with repetitions. What happens 

 the same way again and again and again gives us our feeling of constancy, 

 order, permanence. Things are and they continue to be the same — yesterday, 

 today, and forever. We cannot imagine a time when things were really 

 different, except in detail. With respect to plants and animals specifically, like 

 produces like. We see no exceptions, and we conclude that it must always 

 have been so. 



Yet, from a study of the earth's crust and from a study of what is hap- 

 pening to stars and planets, we know that there must have been a time during 

 the formation of the earth when the temperature was too high for life. The 

 water was probably in the form of vapor, so that the earth was also too dry to 

 support life. No food was available. Sometime later — many many thou- 

 sands of years — living things were present. The scientist wonders what hap- 

 pened during that interval, for it was then that "life" began upon this earth. 



Life from Afar One theory supposes that the first living germs came 

 floating through space from other planets, and found upon the earth a favor- 

 able habitation. Life germs took hold, and in time took on the many forms of 

 plants and of animals. We can imagine spores small enough to be carried 

 through space, pushed by beams of light — some of them falling at last upon the 

 earth and establishing themselves as living protoplasm. This theory has to 

 meet many difficulties. These are: the intense cold in the empty space be- 

 yond the earth, the absence of moisture, the extremely long t'me that it would 

 take anything to come from the nearest system beyond our sun, and perhaps 

 the destructive effects of the ultraviolet light. 



To assume that life came from some other galaxy or solar system is merely 



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