iv MECHANISM AND TELEOLOGY 301 



where it is. It will repay us to examine further into this 

 necessity. It does not arise immediately. We could, for 

 example, take the action of the lever at a given point in 

 its stroke and connect it with the whole configuration of 

 the machine at the same moment. We could then, on 

 purely mechanical principles, trace back this configuration 

 to the preceding configuration and so on. It is only when 

 we ask about the initial step, how this particular machine 

 came into being and why it was set to work, that we are 

 forced outside the mechanism itself to human hands and 

 human minds controlling the whole. The reason why we 

 are thus driven outside is that the machine does not explain 

 itself. Its parts have, apart from their purpose, no intrinsic 

 connection with one another. We can see that this rod 

 works in that socket and is made to fit it, but we see at the 

 same time that it does so only because it is made. The 

 socket, as a piece of metal, does not intrinsically necessitate 

 a rod working through it, nor the rod a socket. They are, 

 as it is sometimes put, quite external, or, in our previous 

 phrase, they are indifferent to one another, and it requires 

 an outside force, the hand of a workman and the brain of 

 an engineer to bring them together. To find that which 

 in physical fact brought them into connection we must 

 go to the purpose, which thus figures as the unitary prin- 

 ciple connecting things otherwise alien. Conversely, as 

 long as we disregard the purpose of a mechanical arrange- 

 ment or configuration we can explain it only by showing 

 bit by bit how each element of it grows out of the corre- 

 sponding element of a previous configuration. There can 

 be no mechanical explanation of a configuration as such, 

 but the reference must always be to an antecedent con- 

 figuration and so ad infinitum. 



Now in the case of the machine, this reference drives us 

 in the end to an external agent. This is due to the indiffer- 

 ence of the parts. One lever does not create another to 

 work with it, nor depend for its growth upon another. 

 Suppose, however, we were to find any arrangement in 

 which externality were overcome, in which the growth and 

 action of the parts were, in fact, mutually dependent, the 

 case would be different. We might then conceive an 



