tradition: the evidence of biology 



In everyday life (as opposed to conferences) we never think 

 about Springs of Action in a general way at all; we think only 

 about the springs o^ particular actions and with the problem of 

 choosing between one action and another. We do not worry 

 about why human beings have propensities for loving and 

 hating, but about why one person loves a second and hates a 

 third. We take it for granted that people need food and take 

 steps to get it, but what is interesting about food-seeking 

 activities of human beings is why they eat this and not that, 

 here and not there, now and not then. It is no great new truth 

 that human beings are ambitious; what is interesting about 

 ambition is why in one person it takes the form of wanting to 

 become a great musician, in another of wanting to raise a large 

 family, and in a third (for this too is an ambition) of wanting 

 to do nothing at all. In these three examples I hope you can 

 see a clear distinction between the propensities underlying 

 certain general kinds of behaviour and the factors which decide 

 that a certain general kind of behaviour shall take a certain 

 particular form. 



Unfortunately, the evidence of biology does not yet run to 

 analysing the sources of particular human actions and decisions: 

 that is a matter for psychology, or perhaps for common sense. 

 But that does not mean that the evidence of biology is un- 

 informative or dull. Tinbergen^ and Lorenz have given us 

 reasons for believing that many kinds of behaviour which seem 

 to us to be peculiarly human are part of a very ancient heritage 

 — 'showing off, for example; playing with dolls; sexual rivalry; 

 and many kinds of '"displacement activity\ in which a thwarted 

 instinctive impulse vents itself in actions of an apparently quite 



1 See N. Tinbergen's The Study of Instinct, Oxford, 1951. My indebted- 

 ness to Tinbergen will be very obvious to anyone who follows the newer 

 research on animal behaviour ('ethology', as it has come to be caUed). 



135 



