"What a noble privilege is it of human reason to attain the knowledge of the supreme Being; and, from the visible works of nature, be enabled to infer so sublime a principle as its supreme Creator? But turn the reverse of the medal. Survey most nations and most ages. Examine the religious principles, which have, in fact, prevailed in the world. You will scarcely be persuaded, that they are any thing but sick men's dreams: Or perhaps will regard them more as the playsome whimsies of monkies in human shape, than the serious, positive, dogmatical asseverations of a being, who dignifies himself with the name of rational."
"Reasoning from the common course of nature, and without supposing any new interposition of the Supreme Cause, which ought always to be excluded from philosophy; what is incorruptible must also be ingenerable. The soul, therefore, if immortal, existed before our birth: And if the former existence noways concerned us, neither will the latter."
"There is not to be found, in all history, any miracle attested by a sufficient number of men, of such unquestioned good sense, education, and learning, as to secure us against all delusion in themselves ... beyond all suspicion of any design to deceive others ... and at the same time attesting facts, performed in such a public manner, and in so celebrated a part of the world, as to render the detection unavoidable."
"We learn the influence of our will from experience alone. And experience only teaches us, how one event constantly follows another; without instructing us in the secret connexion, which binds them together, and renders them inseparable."
"One would appear ridiculous who would say, that it is only probable the sun will rise to-morrow, or that all men must die; thoughit is plain we have no further assurance of these facts than what experience affords us."
"Consciousness never deceives.... We learn the influence of our will from experience alone. And experience only teaches us, how oneevent constantly follows another; without instructing us in the secret connexion, which binds them together, and renders them inseparable."
"Custom, then, is the great guide of human life. It is that principle alone, which renders our experience useful to us, and makes us expect, for the future, a similar train of events with those which have appeared in the past."
"I know with certainty, that [an honest man] is not to put his hand into the fire, and hold it there, till it be consumed: And thisevent, I think I can foretell with the same assurance, as that, if he throw himself out at the window, and meet with no obstruction, he will not remain a moment suspended in the air."
"The sweetest and most inoffensive path of life leads through the avenues of science and learning; and whoever can either remove any obstructions in this way, or open up any new prospect, ought so far to be esteemed a benefactor to mankind."
"Reason, in a strict sense, as meaning the judgment of truth and falsehood, can never, of itself, be any motive to the will, and can have no influence but so far as it touches some passion or affection. Abstract relations of ideas are the object of curiosity, not of volition. And matters of fact, where they are neither good nor evil, where they neither excite desire nor aversion, are totally indifferent, and whether known or unknown, whether mistaken or rightly apprehended, cannot be regarded as any motive to action."
"To invent without scruple a new principle to every new phenomenon, instead of adapting it to the old; to overload our hypothesis with a variety of this kind, are certain proofs that none of these principles is the just one, and that we only desire, by a number of falsehoods, to cover our ignorance of the truth."
"A person, seasoned with a just sense of the imperfections of natural reason, will fly to revealed truth with the greatest avidity:while the haughty Dogmatist, persuaded that he can erect a compleat system of Theology by the mere help of philosophy, disdains any further aid, and rejects this adventitious instructor."
"The end of all moral speculations is to teach us our duty; and, by proper representations of the deformity of vice and beauty of virtue, beget correspondent habits, and engage us to avoid the one, and embrace the other."
"All morality depends upon our sentiments; and when any action or quality of the mind pleases us after a certain manner we say it is virtuous; and when the neglect or nonperformance of it displeases us after a like manner, we say that we lie under an obligation to perform it."
"If morality had naturally no influence on human passions and actions, it were in vain to take such pains to inculcate it; and nothing would be more fruitless than that multitude of rules and precepts with which all moralists abound."
"The proper office of religion is to regulate the heart of men, humanize their conduct, infuse the spirit of temperance, order, andobedience; and as its operation is silent, and only enforces the motives of morality and justice, it is in danger of being overlooked, and confounded with these other motives."