But the little boundaries of so-called health and decay, strength and weakness, as well as all alleged _fixity_ or changelessness of things,—how he had brooded on all that, at that time. And how all thought of fixity in anything had disappeared as a ridiculous illusion intended, maybe, by something to fool man into the belief that his world here, his physical and mental state, was real and enduring, a greater thing than anything else in the universe, when so plainly it was not. But not himself. A mere shadow—an illusion—nothing. On this little roof, here, sitting alone at night or by day in pleasant weather or gray, Saturdays and Sundays when it was warm and because they had no money and no particular place to go, and looking at the stars or the lights of the city or the sun shining on the waters of the little river below,—he had thought of all this. It had all come to him, the evanescence of everything, its slippery, protean changefulness. Everything was alive, and everything was nothing, in so far as its seeming reality was concerned. And yet everything was everything but still capable of being undermined, changed, improved, or come at in some hitherto undreamed-of way—even by so humble a creature as himself, an inventor—and used as chained force, if only one knew how. And that was why he had become a great inventor since—because he had thought so—had chained force and used it—even he. He had become conscious of anterior as well as ulterior forces and immensities and fathomless wells of wisdom and energy, and had enslaved a minute portion of them, that was all. But not here! Oh, no. Later! The sad part of it, as he thought of it now, was that poor little Marie could not have understood a thing of all he was thinking, even if he had explained and explained, as he never attempted to do. Life was all a mystery to Marie—deep, dark, strange—as it was to him, only he was seeking and she was not. Sufficient to her to be near him, loving him in her simple, dumb way, not seeking to understand. Even then he had realized that and begun to condemn her for it in his mind, to feel that she was no real aid and could never be—just a mother-girl, a housewife, a social fixture, a cook, destined to be shoved back if ever he were really successful; and that was sad even then, however obviously true.