Hello, SFIA audio listeners. In this month's Nebula exclusive, big alien theory,

we're asked at the reason alien civilizations might be rare is because most aliens are huge.

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Our knowledge can only be finite, while our ignorance must necessarily be infinite.

Carl Popper

The universe, which others call the library, is composed of an indefinite, perhaps infinite number of hexagonal galleries. In the center of

each gallery is a ventilation shaft bounded by a low railing. For many hexagon one can see the floors

above and below, one after another, endlessly. The arrangement of the galleries is always the same.

Twenty bookshelves, five to each side, line four of the hexagon's six sides, the height

of the bookshelves, floor to ceiling, is hardly greater than the height of a normal librarian.

One of the hexagon's free sides opens onto a narrow sort of vestibule, which in turn opens

on to another gallery, identical to the

first, identical, in fact, to all. To left and right of the vestibule are two tiny compartments.

One is for sleeping, upright, the other for satisfying one's physical necessities. Through this

space, too, there passes a spiral staircase,

which winds upward and downward, into the remotest distance. In the vestibule, there is a

mirror, which faithfully duplicates appearances. Men often infer from this mirror that the library

is not infinite. If it were, what need would there be for that

illusory replication? I prefer to dream that burnish surfaces are a figuration and a promise of the

infinite. Light is provided by certain spherical fruits that bear the name bulbs. There are two of

these bulbs in each hexagon, set crosswise.

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