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from; until the whole world is mapped, even the sea floor, and many 

 individual histories have been teased out of the data, the worldwide 

 picture of plate tectonics can hardly be drawn. Even now, the 

 specialized sciences, with their diverse techniques and conceptual 

 structures, do not often aim directly at the larger questions. There is 

 a kind of disparity between the great end which science, as a whole, 

 seeks - the full understanding of our universe and the human place 

 within it - and the everyday or every decade problems which it can 

 and does solve. The great questions are often put aside for another 

 generation. 



The problem of the origin of life is such a great question. Only 

 in the last decades, since we have acquired a powerful molecular view 

 of life's inner unity and a growing reach into space toward the old 

 history of the planets and the Earth, can we begin to ask that ques- 

 tion in so many words. The story of the growth of that topic within 

 science, and the scale and scope of the community recently engaged 

 with the issue are sketched here. 



The idea of life arising from nonlife, the idea of spontaneous 

 generation, had been commonplace for millennia. One had only to 

 accept the evidence of the senses, thought the ancients: worms from 

 mud, maggots from decaying meat, and mice from old linen. 

 Aristotle had propounded the doctrine, along with Virgil and 

 Lucretius. This teaching was accepted by a long line of western 

 thinkers. Eastern ideas were similar. In the ancient Hindu scriptures 

 life is described as having originated from nonliving matter. The 

 Rig Veda, for example, pointed to the beginnings of life from the 

 primary elements while the Atharva Veda postulated the oceans as 

 the cradle of all living things. 



The first pointed experimental investigation of the concept of 

 spontaneous generation was carried out by Francesco Redi of 

 Florence in 1668. His experiment was as simple as it was decisive. 

 Once the jar of meat was covered with a veil of muslin, no flies could 

 lay eggs on the decaying meat, and therefore it bred no maggots. All 

 life is from the egg! 



With the use of the microscope by Robert Hooke and Anthony 

 Leeuwenhoek (ca. 1660-1700) a new false trail appeared. Many who 

 used the new instrument saw many moving microorganisms grow 

 amidst decaying vegetable matter but they were unable to explain 



