Actually, there are a myriad reasons. (And I can’t think of a single legitimate reason not to read him. Uninformed reasons, yes, and/or reasons based on the faulty assumption that fantasy/SF has nothing to do with reality — or that funny has nothing to do with serious. But legitimate ones? Nope.)

This brief bit from Witches Abroad pretty much boils it down for me. The bare context you need at this point is that a conversation is taking place among three witches. Old Mother Dismass, the subject of this passage, has the ability to see into the future.

“You can’t tell me that’s worth tuppence,” said Old Mother Dismass, from whatever moment of time she was currently occupying.

No one was ever quite sure which it was.

It was an occupational hazard for those gifted with second sight. The human mind isn’t really designed to be sent rocketing backward and forward along the great freeway of time and can become, as it were, detached from its anchorage, seeing randomly into the past and the future and only occasionally into the present. Old Mother Dismass was temporally unfocused. This meant that if you spoke to her in August she was probably listening to you in March. It was best just to say something now and hope she’d pick it up next time her mind was passing through.

The writing is just right; even that “as it were,” which in a lesser writer’s hands might function as mere filler, adds an ironic distance between the author and the things and events which he’s describing.

I love the turnings of the mind behind this passage. Given a common convention of speculative fiction — second sight — just stop. Stop, and ask yourself what it would really mean to have this “gift.” Mightn’t life and thought actually be a little more unpleasantly complicated for the (ha ha) lucky seer than we normally take for granted? How would this power, if someone actually had it, affect those who had to deal every day with its bearer?

Finally, take that whole reductio ad absurdum of a notion and package it up into a supremely funny digression…

Damn. I’d love to be able to do that, and do it repeatedly, over the course of 25+ years (and counting).