It is partly this impatience of obligation which makes a man desirous of giving as requital more than he has received; for otherwise his benefactor has still the superiority of having taken the initiative. But also the worthier motive of affection urges us in the same direction: and here, as in other affectionate services, we do not like too exact a measure of duty; a certain excess falling short of extravagance seems to be what we admire and praise. In so far, however, as conflict of claims makes it needful to be exact, we think perhaps that an equal return is what the duty of gratitude requires, or rather willingness to make such a return, if it be required, and if it is in our power to make it without neglecting prior claims. For we do not think it obligatory to requite services in all cases, even if it be in our power to do so, if the benefactor appear to be sufficiently supplied with the means of happiness: but if he either demand it or obviously stand in need of it, we think it ungrateful not to make an equal return. But when we try to define this notion of ‘equal return,’ obscurity and divergence begin. For (apart from the difficulty of comparing different kinds of services where we cannot make repayment in kind) Equality has two distinct meanings, according as we consider the effort made by the benefactor, or the service rendered to the benefited. Now perhaps if either of these be great, the gratitude is naturally strong: for the apprehension of great earnestness in another to serve us tends to draw from us a proportionate response of affection: and any great pleasure or relief from pain naturally produces a corresponding emotion of thankfulness to the man who has voluntarily caused this, even though his effort may have been slight. And hence it has been suggested, that in proportioning the dues of gratitude we ought to take whichever of the two considerations will give the highest estimate. But this does not seem in accordance with Common Sense: for the benefit may be altogether unacceptable, and it is hard to bind us to repay in full every well-meant blundering effort to serve us; though we feel vaguely that some return should be made even for this. And though it is more plausible to say that we ought to requite an accepted service without weighing the amount of our benefactor’s sacrifice, still when we take extreme cases the rule seems not to be valid: _e.g._ if a poor man sees a rich one drowning and pulls him out of the water, we do not think that the latter is bound to give as a reward what he would have been willing to give for his life. Still, we should think him niggardly if he only gave his preserver half-a-crown: which might, however, be profuse repayment for the cost of the exertion. Something between the two seems to suit our moral taste: but I find no clear accepted principle upon which the amount can be decided.