That the perpetual flower of youth should be the present which mankind received as a reward for their accusation, carries this moral; that the ancients seem not to have despaired of discovering methods, and remedies, for retarding old age, and prolonging the period of human life; but rather reckoned it among those things which, through sloth and want of diligent inquiry, perish and come to nothing, after having been once undertaken, than among such as are absolutely impossible, or placed beyond the reach of the human power. For they signify and intimate from the true use of fire, and the just and strenuous accusation and conviction of the errors of art, that the divine bounty is not wanting to men in such kind of presents, but that men indeed are wanting to themselves, and lay such an inestimable gift upon the back of a slow-paced ass; that is, upon the back of the heavy, dull, lingering thing, experience; from whose sluggish and tortoise-pace proceeds that ancient complaint of the shortness of life, and the slow advancement of arts. And certainly it may well seem, that the two faculties of reasoning and experience are not hitherto properly joined and coupled together, but to be still new gifts of the gods, separately laid, the one upon the back of a light bird, or abstract philosophy, and the other upon an ass, or slow-paced practice and trial. And yet good hopes might be conceived of this ass, if it were not for his thirst and the accidents of the way. For we judge, that if any one would constantly proceed, by a certain law and method, in the road of experience, and not by the way thirst after such experiments as make for profit or ostentation, nor exchange his burden, or quit the original design for the sake of these, he might be an useful bearer of a new and accumulated divine bounty to mankind. That this gift of perpetual youth should pass from men to serpents, seems added by way of ornament, and illustration to the fable; perhaps intimating, at the same time, the shame it is for men, that they, with their fire, and numerous arts, cannot procure to themselves those things which nature has bestowed upon many other creatures. The sudden reconciliation of Prometheus to mankind, after being disappointed of their hopes, contains a prudent and useful admonition. It points out the levity and temerity of men in new experiments, when, not presently succeeding, or answering to expectation, they precipitantly quit their new undertakings, hurry back to their old ones, and grow reconciled thereto.