Science Fiction is a branch of literature that tries to push the borders of the unknown out a little further. It attempts to unveil the future; to imagine worlds lying beyond the next hill, river over ocean (including the ocean of space); to impress vividly upon the reader that the world need not necessarily be the way it happens to be, and that other states of existence are possible besides the one we know. Change is the proclaimed credo of science fiction—so much so that some writers have claimed this essential characteristic to be something that distinguishes SF above all other kinds of fiction. How paradoxical, then, that science fiction should be primarily an English-language phenomenon, at least in the minds of the majority of readers—and not only in the United States, but in Europe as well. A casual observer should expect science fiction to be more international than other kinds of popular fiction, precisely as a result of this stress on change: for isn't it reasonable to assume that the hopes, fears and expectations of people will be different in different countries, their ways of looking at things unlike those in one's own country? And yet the facts point to a different picture; while change is welcomed, obviously not all kinds of change are welcomed: not, for instance, the change that is necessary to adjust to the worlds presented in foreign science fiction which may be alien enough without any deliberate attempt at further estrangement. The late Donald A. Wollheim commented upon this phenomenon in his introduction to Sam J. Lundwall's Science Fiction: What It's All About (New York: Ace Books, 1971):