will be evident, however, that such a method as this cannot be expected to yield more than a rough approximation to the supposed truth. § 7. We must conclude then that our estimate of the hedonistic value of any past pleasure or pain, is liable to an amount of error which we cannot calculate exactly; because the represented pleasantness of different feelings fluctuates and varies indefinitely with changes in the actual condition of the representing mind. We have now to observe that, for similar reasons, even supposing we could adequately allow for, and so exclude, this source of error in our comparison of past pleasures, it is liable to intrude again in arguing from the past to the future. For our capacity for particular pleasures may be about to change, or may have actually changed since the experiences that form the data of our calculation. We may have reached the point of satiety in respect of some of our past pleasures, or otherwise lost our susceptibility to them, owing to latent changes in our constitution: or we may have increased our susceptibility to pains inevitably connected with them: or altered conditions of life may have generated in us new desires and aversions, and given relative importance to new sources of happiness. Or any or all of these changes may be expected to occur, before the completion of the course of conduct upon which we are now deciding. The most careful estimate of a girl’s pleasures (supposing a girl gifted with the abnormal habit of reflection that would be necessary) would not much profit a young woman: and the hedonistic calculations of youth require modification as we advance in years.