By observation, we know somewhat of the economy, action, and nourishment of a finished animal; but we must transfer with great caution that observation to the growth of a foetus in the womb, and still more to the formation of an animalcule in the loins of its male parent.

Nature, we find, even from our limited experience, possesses an infinite number of springs and principles, which incessantly discover themselves on every change of her position and situation.

And what new and unknown principles would actuate her in so new and unknown a situation as that of the formation of a universe, we cannot, without the utmost temerity, pretend to determine.
A very small part of this great system, during a very short time, is very imperfectly discovered to us; and do we thence pronounce decisively concerning the origin of the whole?
Admirable conclusion! Stone, wood, brick, iron, brass, have not, at this time, in this minute globe of earth, an order or arrangement without human art and contrivance; therefore the universe could not originally attain its order and arrangement, without something similar to human art.
But is a part of nature a rule for another part very wide of the former?
Is it a rule for the whole?
Is a very small part a rule for the universe?
Is nature in one situation, a certain rule for nature in another situation vastly different from the former?
And can you blame me, CLEANTHES, if I here imitate the prudent reserve of SIMONIDES, who, according to the noted story, being asked by HIERO, What God was?
desired a day to think of it, and then two days more; and after that manner continually prolonged the term, without ever bringing in his definition or description?
Could you even blame me, if I had answered at first, that I did not know, and was sensible that this subject lay vastly beyond the reach of my faculties?
You might cry out sceptic and railler, as much as you pleased: but having found, in so many other subjects much more familiar, the imperfections and even contradictions of human reason, I never should expect any success from its feeble conjectures, in a subject so sublime, and so remote from the sphere of our observation.

When two species of objects have always been observed to be conjoined together, I can infer, by custom, the existence of one wherever I see the existence of the other; and this I call an argument from experience.

But how this argument can have place, where the objects, as in the present case, are single, individual, without parallel, or specific resemblance, may be difficult to explain.