Why does it seem to me that the intelligence-revolution only happened somewhere between fifty and twenty years ago?
Why has the human race existed for two million years, yet only become intelligent (ten percent of them) in the last fifty or so?
Why are so many humans still incredibly stupid?
How are we still alive with so many of us still so stupid?
(from subject line.) Yes, I believe I do. Come to thing of it, I think a lot of people still do.
Not answering because I do not have enough information on how things seem to you.
I doubt your presupposition here. People have been equipped with the logical faculty and ability to perceive patterns for thousands of years at least. Various social customs and superstitions have led people from past ages to believe in things that now seem stupid. We still form beliefs based on social customs and superstitions, and still believe things that will seem stupid in a hundred years.
Again, I disagree with your assumption. A lot of us are stupid, but I don’t think many of us are incredibly stupid.
Well, we’re stupid enough to stay alive. We’re pretty clever with respect to a lot of the other animals around. That gives us an edge. Of course, now we’ve become bright enough that the leading cause of death is ourselves. 
Agreed. I find the stupidity of others entirely too credible.
Subliminal messages? Of course they don’t work. Who would ever believe (Send me money.) such a preposterous notion?
Weren’t a lot of people still debating the whole Heavy Metal backwards lyrics thing into the early 1990’s?
You are hungry. Eat at McDonald’s. Hamburgers are yummy. Tasty hot fries.
Since Kevin Trudeau’s Natural Cures they don’t want you to know about is selling quite briskly i don’t think that “intelligence revolution” has happened yet.
Yes, Bearflag70, they were. There was a high-profile lawsuit against a metal band (Judas Priest?) that was accused of planting subliminal messages encouraging suicide in their lyrics. The lawsuit was brought by the parents of a teenaged boy who had supposedly spent a great deal of time listening to the band’s music with a friend before the two boys attempted suicide by shotgun. The boy whose parents brought the lawsuit had survived the attempt (with an extremely mangled face).
Hmm, self-inflicted shotgun blast. Seems to me they should have sued the shotgun manufacturer for selling a defective weapon.
To the OP: If you think about it, only 50% of the population is below average intelligence, and average is actually surprisingly capable.
It only seems like they’re more prevalent because they do things that garner themselves attention, like sue metal bands for making their kids shoot themselves or blame natural disasters on gays.
I think the premise of this is flawed: modern humans tend to think of themselves as highly intelligent because of all the fabulous things we do - write books, ue computers, etc. People in the past weren’t less intelligent, though.
Take some stereotypical hunter-gatherer. A modern person might look at them squatting in a hut huddled next to a fire, yet without a chimney to take the smoke out. The modern person’s arrogance comes from having chimneys, or not needing to use fire as evidence of their own higher intelligence, but neither of these things are due to that modern individual. Chimneys were invented millenia ago and non-fire heating systems centuries ago.
Why can the modern person accomplish more or solve more problems? The ability to pass on knowledge and experience through literacy has been extremely valuable and has developed only recently. Even more effective and abstract language probably isn’t all that old. People often mistake this ability to pass on information as intelligence, but it isn’t.
In the same vein, Europeans thought Asians, Africans, and Americans were of lesser intelligence not very long ago. The Europeans proved far more effective at discounting evidence that didn’t fit their preconcieved notions than at demonstrating superior intelligence.
If you could somehow transport a baby from 20,000 years ago to the present, there’s no evidence that it would have any better or worse chance at demonstrating intelligence than a modern baby.
It turns out you don’t need to be all that smart to survive.
And there are a number of factors that have been working lately to try to protect people from the results of their stupidity/innattention/bad luck.
If one were to look at the writings of, say, Euclid from thousands of years ago and, for example, one of your OPs, who would one conclude was stupid? 
Remember when Kevin Nealon used to do that subliminal message guy on Saturday Night Live?
Not only that, but it might help not to be all that smart. A few years back a study on American’s sexual habits revealed that the higher your level of formal education, the fewer children you were likely to have, and the less likely you were to have sex in any given week.
Do you have a Paypal account JThunder?
Clearly, getting such a thing to work would take a much more advanced technique <font size=“1”> <font color=“SlateGray”> Psi Corps is your friend. Trust the Corps. </font> </font>
Yeah, yeah, and Yvan Eht Nioj.
Same ratio of stupid people as always, but with modern communications, they’re just “louder” now. Hail Ranchoth. Worship him, ye sniveling peasants. His word is law.
Oh, yeah. REALLY advanced technique, corpsman.
First, check out the Archives: Does subliminal advertising work?
Second, I don’t quite understand why this was posted in Cafe Society, since it’s not about arts or entertainment. Since there was a column on it, it could go in CoCC, or a debate on human intelligence could push it to Great Debaes, but I’m thinking it’s more aimed at some sort of philosophical rambling, so MPSIMS.
American Splendor:
Guy 1: How smart is she? I dunno. Average, I guess.
Guy 2: Hey man, average is dumb!
I blame social programs and government sponsorship and endorsement of idiotic behavior.