helps to make explicit the essential meaning of 'appears', for 'appears' really means 'appears to us', and 'as perceiving' only repeats the meaning of 'appears' from the side of the perceiving subject as opposed to that of the object perceived. The essential point, however, is thereby brought out that the phrase 'to us as perceiving' essentially relates not to what a thing is, but to what it looks or appears to us. [2] Similarly, we do not say--if we mean what we say--of a man who is colour blind that an object which others call blue _is_ pink to him or to his perception, but that it _looks_ pink to him. What, then, is the proper statement of Kant's view that space is a determination of things only as they appear to us, and not as they are in themselves? It should be said that things are not in reality spatial, but only look or appear spatial to us. It should not be said that they _are_ spatial for our perception, though not in themselves. Thus the view properly stated implies that space is an illusion, inasmuch as it is not a real property of things at all. This implication, however, is precisely the conclusion which Kant wishes to avoid. He takes infinite trouble to explain that he does not hold space and time to be illusions.[3] Though _transcendentally ideal_ (i. e. though they do not belong to things in themselves), they are _empirically real_. In other words, space and time are real relations of _something_, though not of things in themselves. [3] B. 44, 52, 53-4, 62-3, 69-70; M. 27, 31-2, 37-8, 41-2; _Prol._, § 13, Remark iii.