296 DEVELOPMENT AND PURPOSE CHAP. 



and furnace on the other. That is to say, we come to 

 understand our original lever, the fact or part from which 

 we started, as part of an arrangement fixed there to work 

 in with the rest of the arrangement, determined, we may 

 say, by the arrangement as a whole. This line of investi- 

 gation then, as we follow it out, leads to an interpretation, 

 as complete as we can make it, of a system of interacting 

 parts. On the other hand, the system as a whole is governed 

 by a certain purpose, which it serves in its completeness, 

 and only in its completeness. The engine is to draw 

 a train, propel a ship, drive a cotton mill or whatever it 

 may be. The second line of enquiry which teleological 

 investigation opens up is into the nature or value of this 

 purpose, and here again the immediate purpose may be part 

 of a system of values. It may conceivably be an end in 

 itself, or it may be a means to an end, or perhaps a means to 

 more than one end. Thus the immediate purpose of the 

 locomotive is to convey passengers and goods. In a more 

 ultimate sense it is, from one point of view, to facilitate the 

 business or pleasure of the public, from another to assist in 

 earning dividends for the company. Whatever it be, the 

 enquiry into the why of the thing, pursued along this line, 

 must lead us to something, simple or complex, to which as 

 such, and not merely as a means to something else, we can 

 attach definite value. It is, in fact, this last point that is 

 essential to teleological explanation. 



While a conception of value is capable of lighting up an 

 arrangement of indefinitely great complexity, it by no 

 means follows that complexity of arrangement is necessary 

 to the useful application of the idea of value. On the 

 contrary, many actions of extreme simplicity have a teleo- 

 logical explanation in the immediate pleasure attending on 

 them. We walk or swim or look at a view for the pleasure 

 of walking, looking or swimming, and though the biologist 

 may tell us that there is in these things an ulterior value, 

 we feel this to be in a sense a supererogatory explanation. 

 It gives a reason why we should feel pleasure in the kind of 

 exercise in question, but for the exercise itself the pleasure 

 alone is a simple and sufficient reason. Teleological 

 explanation is as such the reference of a fact, an object, a 



