The point is just this. The special science, because special or partial and because at the same time courting scientific character or validity, that is, conformity with reality, must be relative, formal, abstract, artificial, unreal, but also for exactly the same reason it must contrive to admit to its conceptions other view-points than its own. Its own peculiar view-point is relative, but that it may attain actual validity it is bound to overcome its relativity by admitting, secretly perhaps yet not less truly, other points of view; and paradox or contradiction is the natural door for such admissions, the original view-point being tenacious to the last. Physics says: "I will be physics through thick and thin; I will be physics though the heavens fall and though dreadful paradoxes arise"; and in like manner psychology cries aloud: "I will be psychology though I suffer from a splitting dualism for my pains." Have you, gentle reader, never held and held and held to some particular notion about things, modifying the details perhaps little by little, but always imagining yourself strictly loyal to the old, old view, and then suddenly discovered your consciousness alive with contradictions? If you have, you know, possibly [p.100] too well, the natural history of every special science, and also you can sympathize deeply with the hen and her cherished chicks that proved ugly ducklings. The special science, I repeat, must be hospitable, however grudgingly, to strangers, though at the expense of becoming thoroughly divided against itself. Such hospitality is an obligation--call it logical if you will, or moral or metaphysical, for the name matters not if it only suggests coercion--which is not less binding upon the scientific spirit than upon the spirit of racial unity, always urgently present in you and me. You and I may be so special or exclusive as to drive strangers from our doors, but an impulse to call them back and give them entertainment always follows--an impulse that is only the necessary reaction of the expulsion. Humanity is indivisible in spite of our asserted exclusiveness, and nature is indivisible, too, in spite of specialism. Partiality of any sort, along any line, in any field, can never long persist without, though often darkly and indirectly, though by the way of bold, unrecognized, or unconfessed paradox, receiving from outside all that it would exclude. I am not merely repeating. At first, we saw only that the scientific imagination brought to the special science as its working hypotheses certain conserving or compensating conceptions; then, that these conceptions involved treachery to the science that harboured them; but now we are face to face with the fact that their complete, their most effective form is the paradox.