variously affected by a number of things at the same time, but which is not susceptible of itself to an infinite number of modifications. If it should be said that the sensible image of the house is still one, as being one impression, or given result, I answer that the most abstract ideas of a house, and the imperfect recollection of a number of houses is in the same sense one, and a real idea, distinct from that of a tree, though far from being a particular image. Again, it is said, that in conceiving of the idea of man in general, we must conceive a man a particular sign or figure. I would ask first is this to be understood merely of his height, or of his form in general? If the latter, it would imply that we have, wherever we pronounce the word _man_, no ideas at all, or a distinct conception of a man with a head and limbs of a certain extent and proportion, of every turn in each feature, of every variety in the formation of each part, as well as of its distance from every other part, a knowledge which no sculptor or painter ever had of any one figure of which he was the most perfect master, for it would be a knowledge of an infinite number of lines drawn in all directions from every part of the body, with their precise length and terminations. Those who have consigned this business of abstraction over to the senses with a view to make the whole matter plain and easy, have not been aware of what they have been doing. They supposed with the vulgar that it was only necessary to open the eyes in order to see, and that the images produced by outward objects are completely defined, and unalterable things, in which there can be no dimness and confusion. These speculators had no thought but they saw as much of a landscape as Poussin, and knew as much about a face that was before them as Titian or Vandyke would have done. This is a great mistake; the having particular and absolute ideas of things is not only difficult, but impossible. The ablest painters have never been able to give more than one part of nature, in abstracted views of things. The most laborious artists never finished to perfection any one part of an object, or had ever any more than a confused, vague, uncertain notion of the shape of the mouth or nose, or the colour of an eye. Ask a logician, or any common man, and he will no doubt tell you that a face is a face, a nose is a nose, a tree is a tree, and that he can see what it is as well as another. Ask a painter and he will tell you otherwise. Secondly, when it is asserted that we must necessarily have the idea of a particular sign, when we think of any in general, all that is intended by it is, I believe, that we must think of a particular height. This idea it is supposed must be particular and determinate, just as we must draw a line with a piece of chalk, or make a mark with the slides of a measuring rule, in one place and not in the other. I think it may be shewn that this view of the