Our problem melts away when we realize what we mean by this “real size.”  In Chapter V, I have distinguished between apparent space and real space.  Real space is, as was pointed out, the “plan” of the real physical world.  To occupy any portion of real space, a thing must be a real external thing; that is, the experiences constituting it must belong to the objective order, they must not be of the class called mental.  We all recognize this, in a way.  We know that a real material foot rule cannot be applied to an imaginary tree.  We say, How big did the tree seen in a dream seem; we do not say, How big was it really?  If we did ask such a question, we should be puzzled to know where to look for an answer.

And this for a very good reason.  He who asks:  How big was that imaginary tree really? asks, in effect:  How much real space did the unreal tree fill?  The question is a foolish one.  It assumes that phenomena not in the objective order are in the objective order.  As well ask how a color smells or how a sound looks.  When we are dealing with the material we are not dealing with the mental, and we must never forget this.

The tree imagined or seen in a dream seems extended.  Its extension is apparent extension, and this apparent extension has no place in the external world whatever.  But we must not confound this apparent extension with a real mathematical point, and call the tree nonextended in this sense.  If we do this we are still in the old error—­we have not gotten away from real space, but have substituted position in that space for extension in that space.  Nothing mental can have even a position in real space.  To do that it would have to be a real thing in the sense indicated.

Let us, then, agree with the plain man in affirming that the mind is nonextended, but let us avoid misconception.  The mind is constituted of experiences of the subjective order.  None of these are in space—­real space.  But some of them have apparent extension, and we must not overlook all that this implies.

Now for the mind as immaterial.  We need not delay long over this point.  If we mean by the mind the phenomena of the subjective order, and by what is material the phenomena of the objective order, surely we may and must say that the mind is immaterial.  The two classes of phenomena separate themselves out at once.

[1] “The Passions,” Articles 34 and 42.

CHAPTER IX

MIND AND BODY

35.  IS THE MIND IN THE BODY?—­There was a time, as we have seen in the last chapter (section 30), when it did not seem at all out of the way to think of the mind as in the body, and very literally in the body.  He who believes the mind to be a breath, or a something composed of material atoms, can conceive it as being in the body as unequivocally as chairs can be in a room.  Breath can be inhaled and exhaled; atoms can be in the head, or in the chest, or the heart, or anywhere else in the animal economy.  There is nothing dubious about this sense of the preposition “in.”