§3. Can we then, between this Scylla and Charybdis of ethical inquiry, avoiding on the one hand doctrines that merely bring us back to common opinion with all its imperfections, and on the other hand doctrines that lead us round in a circle, find any way of obtaining self-evident moral principles of real significance? It would be disheartening to have to regard as altogether illusory the strong instinct of Common Sense that points to the existence of such principles, and the deliberate convictions of the long line of moralists who have enunciated them. At the same time, the more we extend our knowledge of man and his environment, the more we realise the vast variety of human natures and circumstances that have existed in different ages and countries, the less disposed we are to believe that there is any definite code of absolute rules, applicable to all human beings without exception. And we shall find, I think, that the truth lies between these two conclusions. There are certain absolute practical principles, the truth of which, when they are explicitly stated, is manifest; but they are of too abstract a nature, and too universal in their scope, to enable us to ascertain by immediate application of them what we ought to do in any particular ease; particular duties have still to be determined by some other method.
One such principle was given in chap. i. §3 of this Book; where I pointed out that whatever action any of us judges to be right for himself, he implicitly judges to be right for all similar persons in similar circumstances. Or, as we may otherwise put it, `if a kind of conduct that is right (or wrong) for me is not right (or wrong) for some one else, it must be on the ground of some difference between the two cases, other than the fact that I and he are different persons.' A corresponding proposition may be stated with equal truth in respect of what ought to be done to---not by---different individuals. These principles have been most widely recognised, not in their most abstract and universal form, but in their special application to the situation of two (or more) individuals similarly related to each other: as so applied, they appear in what is popularly known as the Golden Rule, `Do to others as you would have them do to you.' This formula is obviously unprecise in statement; for one might wish for another's co-operation in sin, and be willing to reciprocate it. Nor is it even true to say that we ought to do to others only what we think it right for them to do to us; for no one will deny that there may be differences in the circumstances---and even in the natures---of two individuals, A and B, which would make it wrong for A to treat B in the way in which it is right for B to treat A. In short the self-evident principle strictly stated must take some such negative form as this; `it cannot be right for A to treat B in a manner in which it would be wrong for B to treat A, merely on the ground that they are two different individuals, and without there being any difference between the natures or circumstances of the two which can be stated as a reasonable ground for difference of treatment.' Such a principle manifestly does not give complete guidance---indeed its effect, strictly speaking, is merely to throw a definite onus probandi on the man who applies to another a treatment of which he, would complain if applied to himself; but Common Sense has amply recognised the practical importance of the maxim: and its truth, so far as it goes, appears to me self-evident.
A somewhat different application of the same fundamental principle that individuals in similar conditions should be treated similarly finds its sphere in the ordinary administration of Law, or (as we say) of `Justice'. Accordingly in §1 of chap. v. of this Book I drew attention to `impartiality in the application of general rules', as an important element in the common notion of Justice; indeed, there ultimately appeared to be no other element which could be intuitively known with perfect clearness and certainty. Here again it must be plain that this precept of impartiality is insufficient for the complete determination of just conduct, as it does not help us to decide what kind of rules should be thus impartially applied; though all admit the importance of excluding from government, and human conduct generally, all conscious partiality and `respect of persons'.
The principle just discussed, which seems to be more or less clearly implied in the common notion of `fairness' or `equity', is obtained by considering the similarity of the individuals that make up a Logical Whole or Genus. There are others, no less important, which emerge in the consideration of the similar parts of a Mathematical or Quantitative Whole. Such a Whole is presented in the common notion of the Good---or, as is sometimes said, `good on the whole'---of any individual human being. The proposition `that one ought to aim at one's own good' is sometimes given as the maxim of Rational Self-love or Prudence: but as so stated it does not clearly avoid tautology; since we may define `good' as `what one ought to aim at'. If, however, we say 'one's good on the whole', the addition suggests a principle which, when explicitly stated, is, at any rate, not tautological. I have already referred to this principle as that `of impartial concern for all parts of our conscious life':---we might express it concisely by saying `that Hereafter as such is to be regarded neither less nor more than Now'. It is not, of course, meant that the good of the present may not reasonably be preferred to that of the future on account of its greater certainty: or again, that a week ten years hence may not be more important to us than a week now, through an increase in our means or capacities of happiness. All that the principle affirms is that the mere difference of priority and posteriority in time is not a reasonable ground for having more regard to the consciousness of one moment that to that of another. The form in which it practically presents itself to most men is `that a smaller present good is not to be preferred to a greater future good' (allowing for difference of certainty): since Prudence is generally exercised in restraining a present desire (the object or satisfaction of which we commonly regard as pro tanto `a good'), on account of the remoter consequences of gratifying it. The commonest view of the principle would no doubt be that the present pleasure or happiness is reasonably to be foregone with the view of obtaining greater pleasure or happiness hereafter: but the principle need not be restricted to a hedonistic application; it is equally applicable to any other interpretation of `one's own good,' in which good is conceived as a mathematical whole, of which the integrant parts are realised in different parts or moments of a lifetime. And therefore it is perhaps better to distinguish it here from the principle `that Pleasure is the sole Ultimate Good', which does not seem to have any logical connexion with it.
So far we have only been considering the `Good on the Whole' of a single individual: but just as this notion is constructed by comparison and integration of the different `goods' that succeed one another in the series of our conscious states, so we have formed the notion of Universal Good by comparison and integration of the goods of all individual human---or sentient---existences. And here again, just as in the former me, by considering the relation of the integrant parts to the whole and to each other, I obtain the self-evident principle that the good of any one individual is of no more importance, from the point of view (if I may say so) of the Universe, than the good of any other; unless, that is, there are special grounds for believing that more good is likely to be realised in the one case than in the other. And it is evident to me that as a rational being I am bound to aim at good generally,---so far as it is attainable by my efforts,---not merely at a particular part of it.
From these two rational intuitions we may deduce, as a necessary inference, the maxim of Benevolence in an abstract form: viz. that each one is morally bound to regard the good of any other individual as much as his own, except in so far as he judges it to be less, when impartially viewed, or less certainly knowable or attainable by him. I before observed that the duty of Benevolence as recognised by common sense seems to fall somewhat short of this. But I think it may be fairly urged in explanation of this that practically each man, even with a view to universal Good, ought chiefly to concern himself with promoting the good of a limited number of human beings, and that generally in proportion to the closeness of their connexion with him. I think that a `plain man', in a modern civilised society, if his conscience were fairly brought to consider the hypothetical question, whether it would be morally right for him to seek his own happiness on any occasion if it involved a certain sacrifice of the greater happiness of some other human being,---without any counterbalancing gain to any one else,---would answer unhesitatingly in the negative.
I have tried to show how in the principles of Justice, Prudence, and Rational Benevolence as commonly recognised there is at least a self-evident element, immediately cognisable by abstract intuition; depending in each case on the relation which individuals and their particular ends bear as parts to their wholes, and to other parts of these wholes. I regard the apprehension, with more or less distinctness, of these abstract truths, as the permanent basis of the common conviction that the fundamental precepts of morality are essentially reasonable. No doubt these principles are often placed side by side with other precepts to which custom and general consent have given a merely illusory air of self-evidence: but the distinction between the two kinds of maxims appears to me to become manifest by merely reflecting upon them. I know by direct reflection that the propositions, `I ought to speak the truth', `I ought to keep my promises'---however true they may be---are not self-evident to me; they present themselves as propositions requiring rational justification of some kind. On the other hand, the propositions, `I ought not to prefer a present lesser good to a future greater good', and `I ought not to prefer my own lesser good to the greater good of another',  do present themselves as self-evident; as much (e.g.) as the mathematical axiom that `if equals be added to equals the wholes are equal.'
It is on account of the fundamental and manifest importance, in my view, of the distinction above drawn between (1) the moral maxims which reflection shows not to possess ultimate validity, and (2) the moral maxims which are or involve genuine ethical axioms, that I refrained at the outset of this investigation from entering at length into the psychogonical question as to the origin of apparent moral intuitions. For no psychogonical theory has ever been put forward professing to discredit the propositions that I regard as really axiomatic, by showing that the causes which produced them were such as had a tendency to make them false: while as regards the former class of maxims, a psychogonical proof that they are untrustworthy when taken as absolutely and without qualification true is in my view, superfluous: since direct reflection shows me they have no claim to be so taken. On the other hand, so far as psychogonical theory represents moral rules as, speaking broadly and generally, means to the ends of individual and social good or well-being, it obviously tends to give a general support to the conclusions to which the preceding discussion has brought us by a different method: since it leads us to regard other moral rules as subordinate to the principles of Prudence and Benevolence.