AFAIK, that is empirically established to be true in the US, and seems largely due to the fact that environmental factors that impede full development of intelligence are being addressed. I'm less aware of research on global trends but it seems likely to be generally the same.

As we measure it, yes: https://en.wikipedia.org/wiki/Flynn_effect

Secular declines in cognitive test scores: A reversal of the Flynn Effect: https://www.gwern.net/docs/iq/2016-dutton.pdf

http://www.americanscientist.org/issues/pub/smart-as-we-can-...

I would go further than that even. Human beings are becoming more and more intelligent by the day. I know things today I didn't know yesterday, and certainly much more than I knew a year ago.

Knowing things makes you more knowledgeable, not necessarily more intelligent.

I don't disagree that knowledge is different from intelligence, but surely there's a connection between the two.

It seems to me that intelligence has more to do with the acquisition of knowledge, than whatever you have in possession. If we define intelligence as possession of knowledge, then a dog is more intelligent than humans in many aspects (eg. it can smell a lot better, so it can recognize who was recently in a room that it enters). But if we define intelligence as the ability to acquire new knowledge, then humans are vastly superior to all other species.

In that way, it seems possession of knowledge is more like a symptom of intelligence, rather than being intelligence itself.

Do you claim that they aren't?

I didn't claim anything. I just asked a question.

Yes, as we are yet to define intelligence in a convincing manner.

We are getting better at IQ tests. Exactly what that means is up for debate.

That's the problem with benchmarks. For IQ tests, we measure a small subset of skills, and then extrapolate to make conclusions about other, unmeasured skills.

This works fine as long as the tested humans are unaware of the methodology, because extrapolation doesn't work when the subjects have specialized, specifically, in the subset of skills from which we extrapolate. In other words, if we keep measuring intelligence through IQ tests, sooner or later we will only be good at solving IQ tests -- and that's not very intelligent.

Why don't we have a test for big subset?