16 



FRED M. IT B E R 



boundaries may be either of an experimental or of a theoretical nature. 

 Some are specific and apply to narrow regions or to particular tech- 

 niques; others are general and may encompass an entire field of 

 scientific investigation. An example of the latter is contained in the 

 broad generalizations of the first and second laws of thermodynamics. 

 The first law expresses the well known principle concerning the con- 

 servation of matter and energj^. The second law is something of an 

 oddity in that it is a negative statement which tells what cannot be 



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"He swore he had a pedigree a mile long, and I, 

 like a fool, believed him!" 



Fig;. 2. An experimental scientist should not depend on hearsay. (Courtesy 



Liberty Magazine.) 



done and is therefore not subject to experimental confirmation. For 

 centuries, however, individuals have tried diligently but vainly to 

 disprove it by their ingenious attempts to attain perpetual motion, in 

 other words, a method of obtaining something for nothing. Such 

 people are now referred to as "perpetual motion cranks." They have 

 been ignored by orthodox physicists for a long time, but their recurrent 

 stories still make newspaper copy. 



Of more restricted application but yet an excellent illustration of a 

 boundary imposed by physical theory is the theoretical resolving 

 power of the optical microscope. This somewhat arbitrary limit has 

 been confirmed repeatedly by experiment and tested so thoroughly 



