"There are two kinds of science-fiction reader, who in their extreme forms constitute disjoint reading populations. A pure Population One reader wants scientific ideas and will be tolerant of other flaws provided those ideas are present. A pure Population Two reader will tolerate (or fail to notice) scientific errors but insist on literary virtues. You can tell which population you belong to from what follows…" —High-Tech Futures: How ‘hard sf’ keeps the science in science fiction (WashPost)