Science is not primarily concerned with disproving beliefs which have 

 served to explain the phenomena of life. 



Explanations offered by scientists must be not only plausible, but, in addi- 

 tion, susceptible of being checked against all the facts of observation or ex- 

 periment. 



EXPLORATIONS AND PROJECTS 



1 To find out what explanations different peoples have given concerning the 

 origin of life, read portions of Bulfinch's Age of Fable or of Frazer's Golden 

 Bough. The bibles of different religions or races will suggest other theories of how 

 life began. Have your librarian suggest other sources, such as books on mythology 

 and on the teachings of some of the great philosophers and religious leaders. 



2 To see whether we can get micro-organisms to arise spontaneously in dead 

 organic matter, expose some sterilized bouillon where nothing can get to it from 

 the air, and some under ordinary atmospheric conditions. Compare after a few 

 days or a week. Describe changes that indicate the presence of living matter in 

 either or both of the flasks. 



3 To determine whether maggots (fly larvae) develop spontaneously, expose 

 meat where flies cannot get at it, but where the air can. Place some meat in the 

 bottom of each of three jars; leave one open; cover one with fine gauze and the 

 third with parchment. Keep near an open window or where flies abound. After 

 a week or so, examine each jar carefully; compare results and explain any dif- 

 ferences. 



QUESTIONS 



1 How do we derive our information about life? 



2 In what respects are questions about life essentially different from our 

 questions about particular living things? 



3 What evidence is there that life has always existed ? that it has not always 

 existed ? 



4 What evidence is there to show that life has always remained the same? 

 that it has changed? 



5 What explanations have been proposed of the origin of life? What kind 

 of evidence have we to support or refute these explanations? What chance is 

 there of proving with certainty the truth or falsity of any of these various ex- 

 planations? 



6 In what respects are certain laboratory compounds of organic material like 

 protoplasm? In what respects are they different? 



7 What kinds of answers are possible for questions about the origin of any 

 particular individual or species? for questions about the origin of life as distinct 

 from nonliving matter? How do answers to the first question help us in an- 

 swering the second? 



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