If these errors are successfully avoided, all the labour and pains expended upon problems that are morally right and worth the solving will be fully rewarded. Such a worker in the field of astronomy, for example, was Gaius Sulpicius, of whom we have heard; in mathematics, Sextus Pompey, whom I have known personally; in dialectics, many; in civil law, still more. All these professions are occupied with the search after truth; but to be drawn by study away from active life is contrary to moral duty. For the whole glory of virtue is in activity; activity, however, may often be interrupted, and many opportunities for returning to study are opened. Besides, the working of the mind, which is never at rest, can keep us busy in the pursuit of knowledge even without conscious effort on our part. Moreover, all our thought and mental activity will be devoted either to planning for things that are morally right and that conduce to a good and happy life, or to the pursuits of science and learning.
With this we close the discussion of the first source of duty.
