“When, for the sake of a little more reputation, men can keep brooding over a new fact, in the discovery of which they might possibly have very little real merit, till they think they can astonish the world with a system as complete as it is new, and give mankind a prodigious idea of their judgment and penetration, they are justly punished for their ingratitude to the fountain of all knowledge, and for the want of a genuine love of science and of mankind in finding their boasted discoveries anticipated and the field of honest fame pre-occupied by men who, from a natural ardour of mind, engage in philosophical pursuits, and with an ingenuous simplicity immediately communicate to others whatever occurs to them in their inquiries.” Priestley’s productions, from the very nature of the case make no pretensions to completeness. “In completing one discovery we never fail to get an imperfect knowledge of others of which we could have no idea before, so that we cannot solve one doubt without creating several new ones.” He farther observes that a person who means to serve the cause of science effectually must hazard his own reputation so far as to risk even _mistakes_ in things of less moment. “Among a multiplicity of new objects and new relations some will necessarily pass without sufficient attention; but if a man be not mistaken in the principal objects of his pursuits he has no occasion to distress himself about lesser things. “In the progress of his inquiries he will generally be able to rectify his own mistakes; or if little and envious souls should take a malignant pleasure in detecting them for him and endeavouring to expose him, he is not worthy of the name of a philosopher if he has not strength of mind sufficient to enable him not to be disturbed at it. He who does not foolishly affect to be above the failings of humanity will not be mortified when it is proved that he is but a man.”