A. The Meaning of Tendency

IT is clear that the ethical theory which I have tentatively favoured in the preceding chapter demands a much fuller account of the nature of tendency than I have yet attempted. I shall therefore at this stage desert ethics for a while in order to discuss tendency in the physical, biological, and psychological spheres.

In this discussion two distinct points must be borne in mind, We must inquire more minutely whether there is any truth in the theory that conscious teleological behaviour involves prior unconscious teleological tendency. And further, if this is so, we must inquire whether, in order that unconscious teleological tendency may give rise to conscious striving, there must be cognition of the tendency as objective, or whether the unconscious tendency causes conation independently of cognition by simply occurring in consciousness as a conative act. But first let us consider the nature of tendency in general. A tendency is not an occult power residing in a thing and ‘forcing’ it to act in a particular manner. When we say that a thing tends to act in a certain manner, we mean usually no more than that it would act in that manner if it were not being prevented. From observation of many things of this kind we have induced that they do, as a matter of fact, always act in such a manner unless something hinders them; and therefore we conclude that this thing would so act if it could. One state of activity in the thing, or in the thing and its environment, issues in another state of activity, unless there are complicating circumstances. Thus to say that anything has a certain tendency is, in the first instance, merely to state a descriptive law of its behaviour, not to explain why it behaves. On the other hand, behaviour is in a sense partially explained if it can be shown to be the kind of behaviour that one might expect as the compromise of two or more known tendencies which are applicable to the particular situation, but discrepant with one another.

The tendencies of a thing are objective facts which we may discover; they are not mere conventions or matters of opinion. It is a fact that stones tend to fall, and that certain animals tend to reproduce their kind. Of course, we may make erroneous judgments about tendencies. We may mistakenly judge that a thing has tendencies which it has not, or that it has not tendencies which it has. Or a tendency about which we make judgments may turn out to be a very different kind of tendency from what we thought it to be.

Tendencies, then, are objective facts about things; and the sum of the tendencies of an existent may be said to constitute the nature of that existent. Or perhaps we should rather say that the tendencies of an existent are aspects of, or expressions of, its nature, which is itself unique, and not itself a sum of tendencies.

What kind of being can a tendency have while it is not active? Evidently its being is in some sense merely potential. A thing which tends to behave in a certain way, and is not so behaving, is a thing which would so behave were it not prevented. In the case of a stone supported on a table there may be said to be an inhibited tendency to fall; and this tendency may be said to express itself indirectly in changes in the structure of the stone and the table. But these changes do not themselves constitute the tendency to fall; they are merely a result of it. We need not here discuss the distinction in the physical sphere between kinetic and potential energy, beyond noting that the potential energy of a body is perhaps a hidden form of kinetic energy, which might issue in another, observable, form of kinetic energy were there not some resistant factor. Though the hidden kinetic energy does not itself constitute the tendency to issue overtly in another form, we may say that a tendency to issue overtly does inhere in the hidden kinetic energy. In fact it would issue if it were not prevented.

Perhaps, then, there is, after all, something more in the concept of ‘tendency’ than in the concept of merely descriptive law. To say that a thing would do so and so, if it were not prevented, does very often imply that while it is prevented it is actively tending, thrusting, straining, toward the ‘repressed’ activity. There is, indeed, no implication of conscious striving. But clearly in practice we often mean by tendency something which, though not necessarily conscious, is conceived at least in terms of the experience of physical resistance to our volition. To say that a thing tends to do so and so, then, is to mean, not merely that certain events would occur, were it not for certain other events, but further that the thing is a dynamic thing, that its nature is to act freely in this way, and that while it is prevented it is in a state of tension.

Possibly physical science ought to avoid this obviously anthropomorphic concept of effort, and should mean by a tendency only a descriptive law. For physical tendencies are known only through their issue in overt activity of some sort; so that a tendency is simply an account of the possibility of action. But in psychology, and therefore in biology, which should not fear the help of psychology in this respect, we should frankly admit that the concept of tendency does involve tension. We should mean by a tendency a particular factor in the active nature of a thing, in virtue of which its behaviour is such as to be capable of generalization under a certain law; and in virtue of which, when such behaviour is impossible, the thing remains in a state of tension, directed, though vainly, toward such behaviour.

Let us, however, for the moment leave this matter and briefly consider the relation between tendency and environment. There are two ways of using the word ‘tendency’. Either we may say (a) that an isolated stone has inherently, a tendency to fall, or we may say (b) that, while an isolated stone has in itself alone no tendency to fall, ‘a stone near a planet’ has such a tendency; or, better, that in the complex ‘stone-near-planet’ there arises a tendency for the two members to approach each other. If we adopt the first sense we fall into difficulties. For, applying the principle consistently, we must say that an isolated stone has tendencies to behave in every manner of which a stone is capable in all conceivable situations. Thus it has a tendency ‘to choke a man who attempts to swallow it’, and a tendency ‘to disappoint a man who mistakes it for a mushroom’. But these complicated activities are not in any important sense the outcome of special tendencies in isolated stones. They are the outcome of total situations composed of a stone and a man in a certain mood. Every situation, every complex of existents, gives rise to some activity or other, or issues in a new kind of situation. But if the original situation is further complicated by some conflicting factor, the activity will be different. Yet the original situation may be said to have a tendency to act in the manner in which it would act in isolation. On the other hand, it cannot reasonably be said to have a tendency to act in manners in which it cannot act without the co-operation of an additional factor. We may significantly use the word ‘capacity’ to describe those situations in which, though the thing (whatever it be) has no intrinsic tendency to act in a certain manner. it would so act with the co-operation of certain other factors. Thus, though stones do not tend to choke men, they have the capacity of choking men when they interact in a certain manner with the human body.

The isolated stone, then, has no inhibited or repressed tendency to choke a man or to fall. But in the complex ‘stone-near-planet’ there is a tendency for the two members to approach, even when the tendency is resisted by an intervening table. On the other hand a bomb which is already timed to explode may be said to have a tendency to explode, even though it should be the only thing in the universe. If it were in the centre of the earth and therefore under immense pressure, it would still have a tendency to explode, but a tendency repressed by another factor. But we should not say that a bomb has, in its own nature, a tendency to perform acts more complicated than simple explosion. It has, for instance, no tendency to kill a certain despot, or change the course of history, though, indeed, it has the capacity of doing so in co-operation with a certain kind of environment. We can allow only that a thing has tendencies toward those activities which it can perform of its own nature, without the co-operation of an environment.
B. Biological Tendencies

Unfortunately, however, common usage is opposed to this principle, and there is good reason in its favour. We say that a bird has a tendency to build a nest, and that a man has in his own nature a tendency to eat. Clearly both these activities involve an environment, though in somewhat different manners. In general when we say that an organism has a tendency to behave in a certain manner, we mean that it responds to a certain kind of stimulus (external or internal to the organism) with a certain kind of activity which is possible only in a certain kind of environment. Sex tendencies involve for their normal functioning a partner, and social tendencies involve society. This usage certainly conflicts with our conclusions about the tendencies of the isolated stone. Should we insist that these so-called tendencies of organisms are in truth only capacities? Or is there something peculiar to the nature of organisms which justifies us in supposing that they themselves have tendencies whose functioning demands an environment?

There surely is good reason for saying that an organism’s own nature involves an environment while a stone’s does not.68 Our observation of organisms suggests that their behaviour is regulated in relation to certain ends, such as the preservation and perpetuation of the race. For each species there seems to be a certain normal way of life which involves a certain normal environment. In order to make this point clear let us briefly consider the case of sexual perversion in pigeons.69 Males kept in isolation from females have shown homosexual behaviour; and an individual kept in complete solitude has satisfied its sexual impulses on the human hand. In what sense can we say that pigeons have a ‘tendency’ toward normal sexual intercourse and that the abnormal behaviours are ‘perversions’? If we apply to the pigeon the same principles as we applied to the stone, we must deny that the pigeon itself has any sex tendencies, normal or abnormal. Tendencies emerge from the conjunction of the pigeon and an environment. One kind of environment creates one tendency, and others create other tendencies. Thus normal and abnormal behaviour are set on an equal footing.

But if we take into account all the facts of the behaviour of pigeons, and of organisms in general, we cannot but suspect that, in some important sense, the normal behaviour is not only average, but ‘natural’, and that the abnormal behaviour is ‘unnatural’. We should justify this suspicion by saying that teleological explanations are irresistibly suggested by the behaviour of organisms, and that, in the case of the pigeon, the normal sexual behaviour serves the biological end of procreation, while the perversions serve no end at all. Thus it seems that the pigeon is such that it, of its own intrinsic nature, tends to behave in the normal sexual manner, although it cannot so behave without an appropriate environment. Its body, considered as a teleologically active substance, needs, for the fulfilment of its own intrinsic nature, a certain kind of environment.

Thus the organism’s capacity to reproduce its kind is, after all, not on the same footing as the stone’s capacity to choke a man or disappoint him, although in both cases an environment is necessary for the fulfilment of the capacity. The difference between the two cases lies in the fact that, while no teleological concept is implied in the behaviour of the stone, the behaviour of the organism cannot be even described coherently without teleological concepts. An artificial self-regulating machine, similarly, such as an automatically balancing aeroplane, cannot be coherently described without teleological concepts. In each case there is a complicated form and complicated functioning which is regulated in relation to an end, and is quite incomprehensible if the end is left out of account. Consequently, we are justified in saying that both organism and artificial machine do intrinsically ‘tend’ to fulfil certain ends, even though they cannot function without an appropriate environment.

Thus with regard to machines, we must alter our conclusion about the isolated bomb. For, since it would never have been what it is, had not a destructive purpose taken part in its making, clearly there is a sense in which, even in isolation it does ‘tend’ to destroy life, even if we are not justified in attributing to it a more specific tendency to kill the Czar of Russia or the British Prime Minister. Its nature is definitely regulated in relation to the end of destroying life.

We do not thus imply that, in the case of the machine, there is some mysterious ‘entelechy’ which, interrupting the mechanical behaviour of the parts, directs the whole to a teleological end. We merely observe that the machine, in functioning mechanically, functions also teleologically. Its mechanical parts are so disposed as to function teleologically. Similarly with the organism, in asserting it to have teleological tendencies we do no more than record an observable fact.

It may be that the teleological tendencies of organisms simply arise from a certain configuration of entities which, in other configurations, are manifested only as physical. It may be that, as Dr. Broad puts it, while artificial machines are externally teleological, organisms are in fact (as they certainly appear) internally teleological. Certainly it is very important to insist that while the teleological tendency of the machine is an expression of something more than its own physical nature, and this ‘more’ originates beyond the geometrical confines of the machine itself, in the case of organisms on the other hand the teleology certainly appears to be internal. Anyhow, even if we should, with Rignano, derive all biological tendencies from the tendency of the organism to maintain itself in physiological equilibrium, it remains true that, however they are produced, biological tendencies are, as a matter of fact, teleological, whether externally or internally. 70

Here, however, an important point arises. In the previous chapter we distinguished between physical and teleological activities, by pointing out that, while teleological activity observably involves reference to an end, physical activity does not. Teleological activity, we said, cannot be accounted for simply by reference to the preceding physical state; physical mechanical activity can. It is only because of this reference to a more or less remote future that teleological activity is opposed to physical mechanical activity. The biologist inevitably describes the bird’s straw-gathering and weaving in relation to the end of building a nest, and this in turn in relation to the end of parenthood. Now in some teleological activity the end is more remote and in some less. When great engineering or building projects are undertaken, the end is very remote, and a vast amount of intervening behaviour is explained with reference to this end. But in a sneeze the end is almost immediate. Explanation in terms of the immediately preceding state is more plausible in the latter case than in the former. The end is more obviously regulative in the former than in the latter. But if our theory of teleological activity is correct, there is a regulative end in each case, though in one case the activity obviously varies from time to time according to the exigencies of the situation, while in the other it is stereotyped. In fact, though up to a point it is mechanized, it is mechanized; in service of a certain biological end.

Physical activity is even more stereotyped, and consequently appears even less obviously teleological. But let us remind ourselves that it is as easy to describe the phys............