>>You are being pedantic. I am referring to the future as a
>>whole, not predictions of some particular aspects of the
>>future.
>
>-- oh, not much dispute there. That's why I don't write much >near-future SF.

Science fiction is rather unique in being a type of literature that comes with its own expiration date. Of course, writing far-future fiction doesn't necessarily protect you since the next edition of Nature could knock the pins from beneath any speculative science you might be using.

I think that it was Niven who once wrote a story that relied on the theory that Mercury always kept one face to the sun. If I remember correctly, the very month the story was published it was announced that Mercury does in fact rotate, albeit slowly.

Of course, I don't think that the value of SF is in trying to predict the future. My own view is that SF provides us with useful metaphors and thought experiments by which we can consider various philosophical, social (and so forth) issues. It's a lucky thing when a story does manage to accurately extrapolate some random element of the future but that's really neither the point nor the purpose.