Herbert Spencer (in his _Social Statics_) as a disproof of the
pretentions of utility to be a sufficient guide to right; since (he
says) the principle of utility presupposes the anterior principle, that
everybody has an equal right to happiness. It may be more correctly
described as supposing that equal amounts of happiness are equally
desirable, whether felt by the same or by different persons. This,
however, is not a pre-supposition; not a premise needful to support the
principle of utility, but the very principle itself; for what is the
principle of utility, if it be not that 'happiness' and 'desirable' are
synonymous terms? If there is any anterior principle implied, it can be
no other than this, that the truths of arithmetic are applicable to the
valuation of happiness, as of all other measurable quantities.

[Mr. Herbert Spencer, in a private communication on the subject of the
preceding Note, objects to being considered an opponent of
Utilitarianism; and states that he regards happiness as the ultimate end
of morality; but deems that end only partially attainable by empirical
generalizations from the observed results of conduct, and completely
attainable only by deducing, from the laws of life and the conditions of
existence, what kinds of action necessarily tend to produce happiness,
and what kinds to produce unhappiness. With the exception of the word
"necessarily," I have no dissent to express from this doctrine; and
(omitting that word) I am not aware that any modern advocate of
utilitarianism is of a different opinion. Bentham, certainly, to whom in
the _Social Statics_ Mr. Spencer particularly referred, is, least of all
writers, chargeable with unwillingness to deduce the effect of actions
on happiness from the laws of human nature and the universal conditions
of human life. The common charge against him is of relying too
exclusively upon such deductions, and declining altogether to be bound
by the generalizations from specific experience which Mr. Spencer thinks