n. Finally (6) its _purity_, or the chance of its being unmixed with
the opposite kind; a pure pleasure has no mixture of pain. All the six
properties apply to the case of an individual person; where a plurality
are concerned, a new item is present, (7) the _extent_, or the number
of persons affected. These properties exhaust the meaning of the terms
expressing good and evil; on the one side, happiness, convenience,
advantage, benefit, emolument, profit, &c.; and, on the other,
unhappiness, inconvenience, disadvantage, loss, mischief, and the like.

Next follows, in Chapter V., a classified enumeration of PLEASURES AND
PAINS. In a system undertaking to base all Moral and Political action
on the production of happiness, such a classification is obviously
required. The author professes to have grounded it on an analysis of
human nature, which analysis itself, however, as being too
metaphysical, he withholds.

The simple pleasures are:--1. The pleasures of sense. 2. The pleasures
of wealth. 3. The pleasures of skill. 4. The pleasures of amity. 5. The
pleasures of a good name. 6. The pleasures of power. 7. The pleasures
of piety. 8. The pleasures of benevolence. 9. The pleasures of
malevolence. 10. The pleasures of memory. 11. The pleasures of
imagination. 12. The pleasures of expectation. 13. The pleasures
dependent on association. 14. The pleasures of relief.

The simple pains are:--1. The pains of privation. 2. The pains of the
senses. 3. The pains of awkwardness. 4. The pains of enmity. 5. The
pains of an ill name. 6. The pains of piety. 7. The pains of
benevolence. 8. The pains of malevolence. 9. The pains of the memory.
10. The pains of the imagination. 11. The pains of expectation. 12. The
pains dependent on association.

We need not quote his detailed subdivision and illustration of these.
At the close, he marks the important difference between
_self-regarding_ and _extra-regarding_; the last being those of
benevolence and of malevolence.

In a long chapter (VI.), he dwells on CIRCUMSTANCES INFLUENCING
SENSIBILITY. They are such as the following:--1. Health. 2. Strength.
3. Hardiness. 4. Bodily imperfection. 5. Quantity and Quality of
knowledge. 6. Strength of intellectual powers. 7. Firmness of mind. 8.
Steadiness of mind. 9. Bent of inclination. 10. Moral sensibility. 11.
Moral biases. 12. Religious Sensibility. 13. Religious biases. 14.
Sympathetic Sensibility. 15. Sympathetic biases. 16. Antipathetic
sensi