How to draw the line between judgments of this kind, which are judgments of perception, and those which are not, I do not know. That is to say, I do not know what conditions must be fulfilled in order that I may be truly said to be _perceiving,_ by sight or touch, such things as that that is a door, this is a finger, and not _merely_ inferring them. Some people may no doubt think that it is very unphilosophical in me to say that we _ever_ can perceive such things as these. But it seems to me that we do, in ordinary life, constantly talk of _seeing_ such things, and that, when we do so, we are neither using language incorrectly, nor making any mistake about the facts--supposing something to occur which never does in fact occur. The truth seems to me to be that we are using the term "perceive" in a way which is both perfectly correct and expresses a kind of thing which constantly does occur, only that some philosophers have not recognised that this is a correct usage of the term and have not been able to define it. I am not, therefore, afraid to say that I do now perceive that that is a door, and that that is a finger. Only, of course, when I say that I do, I do not mean to assert that part of what I "perceive," when I "perceive" these things, may not be something which, in an important sense, is known to me only by inference. It would be very rash to assert that "perception," in this sense of the word, entirely excludes inference. All that seems to me certain is that there is an important and useful sense of the word "perception," which is such that the amount and kind of inference, if inference there be, which is involved in my present perception that that is a door, is no bar to the truth of the assertion that I do perceive that it is one. Vast numbers, then, of the kind of judgments with which I propose to deal seem to me to be, in an important and legitimate sense, judgments of perception; although I am not prepared to define, any further than I have done, what that sense is. And though it is true that the questions which I shall raise apply just as much to those of them which are not judgments of perception as to those which are, it is, of course, also true that they apply just as much to those which are as to those which are not; so that I shall be really dealing with a large and important class among judgments of perception.