I don't know about the rest of you, but I find young people today very refreshing. Let's look at 18 year-olds -- the impressionable college freshmen, who could be infected by their dopey professors. If they begin freshman year just 1 year after the theory's peak, the idea is still very popular, so they'll get infected. If we allow, say 5 years of cooling off and decay, professors won't talk about it so much, or will be use a less strident tone of voice, so that only the students who were destined to latch on to some stupid theory will get infected. Depending on the trend, this makes the safe cohort born in 1975 at the oldest (for Marxism), or 1989 at the youngest (for social constructionism). And obviously even among safe cohorts, some are safer than others -- people my age (27) may not go in for Marxism much, but have heard of it or taken it seriously at some point (even if to argue against it intellectually). But 18 year-olds today weren't even born when Marxism had already started to die.