I have said that Certitude, whether in human or divine knowledge, is attainable as regards general and cardinal truths; and that in neither department of knowledge, on the whole, is certitude discredited, lost, or reversed; for, in matter of fact, whether in human or divine, those primary truths have ever kept their place from the time when they first took possession of it. However, there is one obvious objection which may be made to this representation, and I proceed to take notice of it. It may be urged then, that time was when the primary truths of science were unknown, and when in consequence various theories were held, contrary to each other. The first element of all things was said to be water, to be air, to be fire; the framework of the universe was eternal; or it was the ever-new combination of innumerable atoms: the planets were fixed in solid crystal revolving spheres; or they moved round the earth in epicycles mounted upon circular orbits; or they were carried whirling round about the sun, while the sun was whirling round the earth. About such doctrines there was no certitude, no more than there is now certitude about the origin of languages, the age of man, or the evolution of species, considered as philosophical questions. Now theology is at present in the very same state in which natural science was five hundred years ago; and this is the proof of it,—that, instead of there being one received theological science in the world, there are a multitude of hypotheses. We have a professed science of Atheism, another of Deism, a Pantheistic, ever so many Christian theologies, to say nothing of Judaism, Islamism, and the Oriental religions. Each of these creeds has its own upholders, and these upholders all certain that it is the very and the only truth, and these same upholders, it may happen, presently giving it up, and then taking up some other creed, and being certain again, as they profess, that it and it only is the truth, these various so-called truths being incompatible with each other. Are not Jews certain about their interpretation of their law? yet they become Christians: are not Catholics certain about the new law? yet they become Protestants. At present then, and as yet, there is no clear certainty anywhere about religious truth at all; it has still to be discovered; and therefore for Catholics to claim the right to lay down the first principles of theological science in their own way, is to assume the very matter in dispute. First let their doctrines be universally received, and then they will have a right to place them on a level with the certainty which belongs to the laws of motion or of refraction. This is the objection which I propose to consider.