"The methods of Ethics" by Henry Sidgwick,1874

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Modern man uses three different methods of ethics,
three ways of resolving moral problems :
egoism,
intuitionism,and
utilitarianism.
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Egoistic hedonism,
the theory that one ought to seek his own pleasure,
is one of the natural methods of ethics ;
its primary disadvantage is the difficulty of measuring and evaluating pleasures.
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The ethics of right and duty employs an a priori method,
utilizing intuition,
or direct cognition,
as a way of discovering duties ;
but it is difficult to find moral principles
that do not need qualification and
that do not admit exceptions.
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Certain moral principles are manifestly true :
the principle of impartiality,
the principle of prudence,and
the principle of benevolence.
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Utilitarianism is true to the principles of impartiality and benevolence ;
but it is difficult to recognize egoism and utilitarianism.
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