has also some foundation in nature, as we shall see afterwards.

As to the obligations which the male sex lie under, with regard to
chastity, we may observe, that according to the general notions of the
world, they bear nearly the same proportion to the obligations of women,
as the obligations of the law of nations do to those of the law of
nature. It is contrary to the interest of civil society, that men
should have an entire liberty of indulging their appetites in venereal
enjoyment: But as this interest is weaker than in the case of the female
sex, the moral obligation, arising from it, must be proportionably
weaker. And to prove this we need only appeal to the practice and
sentiments of all nations and ages.

PART III OF THE OTHER VIRTUES AND VICES

SECT. I OF THE ORIGIN OF THE NATURAL VIRTUES AND VICES

We come now to the examination of such virtues and vices as are entirely
natural, and have no dependance on the artifice and contrivance of men.
The examination of these will conclude this system of morals.

The chief spring or actuating principle of the human mind is pleasure or
pain; and when these sensations are removed, both from our thought and
feeling, we are, in a great measure, incapable of passion or action, of
desire or volition. The most immediate effects of pleasure and pain are
the propense and averse motions of the mind; which are diversified
into volition, into desire and aversion, grief and joy, hope and fear,
according as the pleasure or pain changes its situation, and becomes
probable or improbable, certain or uncertain, or is considered as out of
our power for the present moment. But when along with this, the objects,
that cause pleasure or pain, acquire a relation to ourselves or others;
they still continue to excite desire and aversion, grief and joy: But
cause, at the same time, the indirect passions of pride or humility,
love or hatred, which in this case have a double relation of impressions
and ideas to the pain or pleasure.

We have already observed, that moral distinctions depend entirely on
certain peculiar sentiments of pain and pleasure, and that whatever
mental quality in ourselves or others gives us a satisfaction, by the
survey or reflection, is of course virtuous; as every thing of this
nature, that gives uneasiness, is vicious. Now since every quality in
ourselves or others, which gives pleasure, always causes pride or love;
as every one, that produces uneasine