356 DEVELOPMENT AND PURPOSE CHAP. 



admission of the inadequacy of mechanics to explain 

 Reality. So much in passing, but let us note for our 

 purpose that the reason why heat is imperfectly available 

 for the purpose of restoring an equivalent of mechanical 

 energy is understood to be the random and chaotic char- 

 acter of the molecular movements by which, physically 

 speaking, it is constituted. If in the equilibrium which 

 yields a store of potential energy, we have opposed forces 

 cancelling one another and so yielding a zero of any 

 apparent effect or real change, in heat we appear to have 

 a chaos of movements producing no combined effect 

 because not reinforcing one another in any given direction, 

 but working against or across one another to no certain end. 

 As soon as we can concentrate heat in sufficient amount 

 upon, say, a certain mass of water, we get a definite series 

 of distinct changes and the evolution of steam which can 

 do mechanical work. 



These mechanical considerations are of value to us 

 mainly as yielding a hint of the true relation between the 

 potential and the actual in development. We find that on 

 the mechanical plane, (i) the energy operating in any pro- 

 cess of change always pre-exists, but the forces possessing 

 this energy have been inhibited by counter forces of equal 

 energy until the process of change began; (2) that what the 

 physicists call available energy, and what we may consider 

 as energy in a relatively developed stage, is the energy of 

 forces operating in some orderly way, that is, with some 

 assignable direction or relation between the phases of 

 change which they determine, while the same quantum of 

 unavailable, or, as we may call it, relatively undeveloped 

 energy is that of forces which operate in no concert with 

 one another, not reinforcing one another, but in random 

 cross currents that tend to no specific result. In effect, 

 they tend to cancel one another as do the counteracting 

 forces in stored energy. We then see that even at this 

 stage, that which appears higher or more developed consists 

 in a process in which we can recognise something that we 

 call at least an order, and that is some arrangement of parts 

 or phases of a process so as together to constitute a whole 

 of distinct character. Such an order involves either the 



