It is in this sense also that we use the word when we say that the object seen with the naked eye and the object seen through a telescope or under a microscope are the same. If I look at a distant object with the naked eye and then look at it through a telescope, what I actually see (or what is actually in the sense) is in the two cases very different. But just as seeing an object from a distance with the naked eye, I may walk towards it and substitute for the dim and vague percept which I first had a series of percepts increasing in clearness and ending in one which I regard as altogether satisfactory, so I may substitute at once this clear percept for the dim one, by the use of the telescope, and may know that it properly belongs to the series which, taken as a whole, constitutes my notion of the object. This I may know from the relations which this percept bears to the other percepts of the series, and which allow me to pass in my inferences from it to them as I can from any one of them to another. If, seeing a dim object upon the horizon, I raise a telescope and through it perceive the figure of a man, I know that I could have had a similar percept without any telescope by simply approaching the object. Conversely, on perceiving a man near at hand, I know I could have a similar percept from a distance by looking through a telescope. I call the man seen through the telescope the same as the man seen with the naked eye, for the same reason as I call the man seen by the eye at a distance the same with the man seen near at hand.