REMARKS TO THE STUDENT 



The Meaning of Laboratory Study in Zoology. — As the laboratory 

 work undertaken in a course in zoology may be new to the student, a 

 word may be said regarding its nature and significance. The basis for 

 all scientific knowledge is first-hand examination of objects in nature 

 or in the laboratory. Intelligent men no longer dispute over the num- 

 ber of teeth the horse has and cite as authority the references to horses 

 in the Bible, as was done in the Middle Ages, or appeal to the writings 

 of Aristotle. They look in a horse's mouth and see for themselves; or 

 if a horse is not available, they consult the works of men who have 

 examined horses and who, it is thought, have truthfully recorded their 

 observations. The strength of all scientific knowledge rests upon the 

 fact that men have seen for themselves, provided, of course, that they 

 have taken the time and trouble to see correctly. Where it is impos- 

 sible to observe the facts at first hand we take the recorded observa- 

 tions of others, on the assumption that we could observe what they 

 say they observed had we the opportunity. But all such knowledge 

 rests upon second-hand authority and can never be so convincing as 

 that of our own senses, provided, of course, that we are trained for 

 such observation. 



To illustrate from other fields, when we study English literature 

 the best method is to read the writings of English authors and not 

 merely to read what someone else says about what these authors have 

 said and how they have written. It is desirable to be guided in such 

 study by a competent teacher and, after reading an author, to know 

 what critics have said regarding his work; but there can be no substi- 

 tute for the study of the original sources, which in this instance are 

 the writings themselves. Again, in the study of history the original 

 source of information is not the textbook, as so many people suppose. 

 Elementary textbooks in history are sometimes based entirely upon 

 second-hand and even third- or fourth-hand knowledge of the facts, 

 with resulting distortions. The original sources in history are the rec- 

 ords of past events, made at the time of their occurrence, and other 

 historic documents; even these are often incomplete and may be in- 

 accurate. If we want to understand the Constitution of the United 

 States, we will do well to begin by reading the document itself and 



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