6 5 o SCIENCE PROGRESS 



available energy of the universe becomes unavailable. With 

 every natural phenomenon that occurs the number of phenomena 

 that may occur in the future becomes appreciably less. " Every 

 irreversible transformation leaves an indelible imprint somewhere 

 or other on the progress of events in the universe considered 

 as a whole." 



Thus there is a tendency or direction in the progress of in- 

 organic happening. Energy is continually being degraded, 

 continually passes from the available into the unavailable form. 

 With every such transformation the number of things that may 

 happen in our universe in the future becomes less. The universe 

 tends towards a limit which is the cessation of all phenomena — 

 universal physical death. There is nothing fanciful or meta- 

 physical in this conclusion. It is a sound deduction from the 

 results of physical science. It is the plain outcome of our 

 experience. 



And yet it is perfectly clear that we cannot extend it, a priori, 

 to the universe as a whole. We must extend universally the law 

 of the conservation of energy — it is unthinkable that it cannot 

 apply to all that exists. If we imagine, literally, that the sum of 

 available energy in the universe was infinite, then the fall of 

 available energy is asymptotic to time considered as the inde- 

 pendent variable. But we must also regard time as infinite, that 

 is, we must think of the universe as having, literally, no begin- 

 ning and no end. Obviously, we are only juggling with words 

 in these statements. Infinite time is really time that has 

 as great a duration as we please to conceive. Then in the lapses 

 of duration that lie in the past of our universe the limit to the 

 fall of available energy must have been attained if the second 

 law be universally true. But we look out upon an universe 

 which is still the theatre of inorganic phenomena. The second 

 law cannot, then, be universally true, like the first law is 

 universally true. But it is true of all that comes within our 

 experience. 



Thus we come to an impasse, for two aspects of our experi- 

 ence seem to be flatly contradictory to each other. On the one 

 hand the results of experimental physics show us an universe in 

 which there is a progressive degradation of energy, that is, an 

 energetic system which had a beginning and will come to an 

 end. On the other hand experience also shows us an universe 

 in which natural phenomena still occur, and for which we can 



