Behind all this bad behaviour was an insecurity magnificent in scope, metaphysical in nature. Space was big, and the boys from Earth were awed despite themselves by the things they found there: but worse, their science was a mess. Every race they met on their way through the Core had a star drive based on a different theory. All those theories worked, even when they ruled out one another's basic assumptions. You could travel between the stars, it began to seem, by assuming anything [. . . .] It was affronting to discover that. So when they fetched up on the edge of the Tract, looked it in the eye, and began to despatch their doomed entradas, the Earthlings were hoping to find, among other things, some answers. They wondered why the universe, which seemed so harsh on top, was underneath so pliable. Anything worked. Wherever you looked, you found. They were hoping to find out why.