The reason why we admit the inference flowing from our examination in the second instance, and so onward, with less scrupulosity and scepticism than in the first, is that there is a strict resemblance and analogy in the two cases. Experience is the basis of our conclusions and our conduct. I strike against a given object, a nail for example, with a certain degree of force, because I have remarked in myself and others the effect of such a stroke. I take food and masticate it, because I have found that this process contributes to the sound condition of my body and mind. I scatter certain seeds in my field, and discharge the other functions of an agriculturist, because I have observed that in due time the result of this industry is a crop. All the propriety of these proceedings depends upon the exact analogy between the old case and the new one. The state of the affair is still the same, when my business is merely that of an observer and a traveller. I know water from earth, land from sea, and mountains from vallies, because I have had experience of these objects, and confidently infer that, when certain appearances present themselves to my organs of sight, I shall find the same results to all my other senses, as I found when such appearances occurred to me before. But the interval that divides the objects which occur upon and under the earth, and are accessible in all ways to our examination, on the one hand, and the lights which are suspended over our heads in the heavens on the other, is of the broadest and most memorable nature. Human beings, in the infancy of the world, were contented reverently to behold these in their calmness and beauty, perhaps to worship them, and to remark the effects that they produced, or seemed to produce, upon man and the subjects of his industry. But they did not aspire to measure their dimensions, to enquire into their internal frame, or to explain the uses, far removed from our sphere of existence, which they might be intended to serve. It is however one of the effects of the improvement of our intellect, to enlarge our curiosity. The daringness of human enterprise is one of the prime glories of our nature. It is our boast that we undertake to "measure earth, weigh air, and state the tides." And, when success crowns the boldness of our aspirations after what vulgar and timorous prudence had pronounced impossible, it is then chiefly that we are seen to participate of an essence divine.