Proof.- The first and only, foundation of virtue, or the rule of right
living is (IV:xxii.Coroll. and IV:xxiv.) seeking one's own true interest.
Now, while we determined what reason prescribes as useful, we took no
account of the mind's eternity, which has only become known to us in this
Fifth Part. Although we were ignorant at that time that the mind is eternal,
we nevertheless stated that the qualities attributable to courage and high-
mindedness are of primary importance. Therefore, even if we were still
ignorant of this doctrine, we should yet put the aforesaid precepts of
reason in the first place. Q.E.D.
Note.- The general belief of the multitude seems to be different. Most
people seem to believe that they are free, in so far as they may obey their
lusts, and that they cede their rights, in so far as they are bound to live
according to the commandments of the divine law. They therefore believe that
piety, religion, and, generally, all things attributable to firmness of
mind, are burdens, which, after death, they hope to lay aside, and to
receive the reward for their bondage, that is, for their piety, and
religion; it is not only by this hope, but also, and chiefly, by the fear of
being horribly punished after death, that they are induced to live according
to the divine commandments, so far as their feeble and infirm spirit will
carry them.
If men had not this hope and this fear, but believed that the mind perishes
with the body, and that no hope of prolonged life remains for the wretches
who are broken down with the burden of piety, they would return to their own
inclinations, controlling everything in accordance with their lusts, and
desiring to obey fortune rather than themselves. Such a course appears to me
not less absurd than if a man, because he does not believe that he can by
wholesome food sustain his body for ever, should wish to cram himself with
poisons and deadly fare; or if, because he sees that the mind is not eternal
or immortal, he should prefer to be out of his mind altogether, and to live
without the use of reason; these ideas are so absurd as to be scarcely worth
refuting.
Prop. XLII. Blessedness is not the reward of virtue, but virtue
itself ; neither do we rejoice therein, because we control our
lusts, but, contrariwise, because we rejoice therein, we are able
to control our lusts.