That's not exactly the idea. See http://en.wikipedia.org/wiki/Flynn_effect http://en.wikipedia.org/wiki/Flynn_effect Maybe a full society is getting used to th

That's not exactly the idea. See http://en.wikipedia.org/wiki/Flynn_effect http://en.wikipedia.org/wiki/Flynn_effect Maybe a full society is getting used to the tests, or maybe the tests are biased. Even with you example (considering repetitive test at the same time on 2 person from the same society), it could show many things: a) that the measurement is flawed b) that you should retest A to see if he also get better scores c) failing that, A has a fixed IQ score while B can improve d) if A improves too what's the limit? Finally, "it's clear that subject A is superior intellectually " - even if B would get say 120 on its final test while A ends with 118??