Leftists are great projectors (tending to see their own faults in others) so to know what is true of them, you just have to look at what they say about conservatives. They even accuse conservatives of projection! So they are always trawling for utterances by conservatives that they can characterize as "hate speech", even though they themselves can hardly open their mouths without pouring out hatred of all those who oppose them.
One of their most constant ploys is to accuse conservatives of being stupid and they have done it so often that conservatives seem to be somewhat abashed by it and rarely treat it as the projection it is. For the record, the ONLY adult general population survey I know of that obtained both IQ scores and a record of political attitudes was Martin's study (which I helped write up for the academic journals). And that study showed that it was LEFTISTS who were most likely to be dumb.
One reason why the accusation that conservatives are dumb gains some weight is the great preponderance of Leftists among professors. That overlooks, however, that the situation was not always thus. Up until the 1960s, the professoriate was in general politically moderate. There were of course exceptions. The elite universities have always tended Left. The best known examples of that are England's two great universities, Oxford and Cambridge. We have all I think heard of the Cambridge spies (Philby et al.), and the Bloomsberries were far Left too. Such leftism can perhaps most economically be described as a "spoilt brat" syndrome. Less well known is the prewar fascination of Harvard with Nazism -- which was a popular form of socialism in its day.
The general moderation of the pre-1960s professoriate was however its undoing. Precisely because of its moderation, it came under ferocious attack from the 1960s student radicals and it responded in a typically moderate way -- apologetically. Curricula were revised in response to the radical demands and more and more Leftists were hired and promoted. And when in the course of time the radical academics so appointed rose in seniority and power, they behaved in a typically unscrupulous way and used their power to squeeze out as many conservatives from academe as they could. So smart conservatives these days go on to get rich in business while the Leftist academics fume away in their ivory towers!
Perhaps most amusingly, however, it should be noted that the Dems and the GOP split the college-educated vote about equally in the last Presidential election. In other words, about half of the people whom the Leftist professors themselves have certified as academically able in fact vote GOP!
The intellectual poverty of the Left shows itself very clearly in their lack of ideas. The only way that they can ever think of for bringing about their desired utopias is the brutishly simply one of FORCING people to behave in the "right" way, by way of legislation in democatic societies or on pain of death in Communist societies.
We have an excellent example of such brainlessness in a 2006 article which argues that the U.S. Left needs to become more socialist. The article consists of nothing but one long wail about the injustices of the world and simply ASSERTS that socialism is the answer -- with no supportive reasoning at all about HOW socialism might fix things -- which is all the more remarkable given the known FAILURES of socialism to fix anything. A few illustrative quotes:
"With corporate capitalism everywhere in command, the outlook is for increased poverty, more environmental degradation, ever more uneven distribution of resources and the undermining of traditional societies and ways of life... Doing battle against the prevailing inequality means invoking the idea that we all belong to a community, as opposed to the illusion, voiced famously by Thatcher, that "there is no society, only individuals." ... On the road to shaping an alternative, the left might respond with a time-honored socialist insight, namely that "I" only exists within a "we," and that unless we look out for everyone, no one is secure.
Note the non sequitur in the last sentence. It is reasonable enough to say that "I" only exists within a "we" but such a statement is only trivially true. Our socialist friend, however seems to think that the truth concerned also implies that "unless we look out for everyone, no one is secure". But England and early America existed in excellent security long before there was any welfare legislation! It is true that private charity at that time looked after the less fortunate but I don't think that private charity is what our socialist friend is advocating!
And another counterfactual assertion above is that capitalism will increase poverty. Since capitalism is provably the the best and surest way of increasing wealth, the statement is deliberately wrongheaded. And it is of course the advanced capitalist societies that have done most to clean up their environment and prevent further degradation of it. You have to be devoid of all knowledge and understanding of how the world actually works (and has worked) to spout the nonsense that our brainless socialist does.
So if Leftists are smart, it certainly does not show in much of their thinking.
As Wray Herbert points out, it would be surprising if one did not see one's own views as more intelligent. So who is right? Is there really an underlying IQ difference between Left and Right?
For a long time the only study I knew of which looked at actual IQ evidence was one that I mentioned briefly above and which I myself helped to write up in the 1970's: Martin's study. That study looked at clearly Leftist attitudes such as the following:
* Most people who are leaders in the world today got there by crooked or sneaky means.
* There isn't really very much your parents or older people can tell you that will help you get along in the world nowadays.
* The best school system is one that is democratic and treats all the pupils exactly alike.
* Complete freedom is the best way to bring up a child if you want it to be free and active.
* Most so-called "juvenile delinquency" is really just "youthful exuberance" and should not be punished.
* One of the best attitudes a young person can learn is that "nothing is sacred."
So who tended to agree with statements like that? The smarties or the dummies? It was the dummies!
Time marches on, however, and another study has recently emerged which looks at the same question. Deary et al. (2008) did quite a powerful study of a British population which came to exactly opposite conclusions. Wray Herbert sums up the study in layman's language.
So how come? A clue is to be found in the fact that the Deary et al. study reported that education was a major factor in the relationship. It was the fact that more intelligent people had more education that produced the relationship. It was education that made you Leftist, not IQ. Anybody who knows how Leftist the educational system is these days will not be surprised to hear that all that Leftist brainwashing had some effect.
But education was not the whole of the story. There was still some effect on attitudes due to IQ alone. But what the education results alert us to is the importance of the overall mental environment of the people surveyed. Deary's sample were all born in 1970. The Martin sample was interviewed in the early 1960s and covered a representative age range but would on average have been born in the mid-1930s. That is a very different group of people -- people who have grown up into very different mental environments. And just the difference in interview dates -- the early 1960s versus the early 2000s -- would account for a lot. A lot has changed over the last 40 years.
In particular, the great attitudinal upheaval of the late 1960s had not happened for Martin's sample and the very expression "political correctness" would have been incomprehensible to them. In short, the cultural attitudes of the modern day world are very different from the attitudes that prevailed before the upheavals of the '60s. I was there in the 60s. I remember the upheavals concerned very well. And the defeat of Soviet Communism ratcheted up the cultural changes even further. When it became clear that Leftists had lost the economic argument (over socialism versus capitalism), they turned their energies onto cultural questions -- promoting homosexuality, attacking marriage etc. The end result is that we now live in a world where the prevailing cultural attitudes are MUCH more Leftist than they once were.
So it is clear why the Martin and the Deary results differ. Smarter people are more aware of the values that are regarded as "correct" in the world about them. What smarter people said in the 60s was conservative because conservative values were the default assumption then. What smarter people said in the 2000s was Leftist because Leftist values have now become the default assumptions in conversations about such things -- and the default assumptions in the media most particularly.
So what the Deary results show when taken in conjunction with the Martin results is not that smart people are Leftists but rather that smart people are more sensitive to the thinking of people around them.
Is the short list of attitudes from Martin's study above really Leftist? Libertarians would also agree with some of the statements listed. Libertarians are however only a tiny fraction of the population and libertarianism was essentially unknown in Australia at the time. It still largely is, in fact. So a libertarian influence on the results can be excluded.
The statements listed are very similar to other statements that were characteristically Leftist at the time. The underlying theme of the items was intended by their author to be a rejection of authority and it should be noted that another Australian questionnaire which systematically surveyed attitudes to authority in 1969 found that attitude to authority correlated even more strongly with political party choice (r = .43) than it did attitude to innovation (.33). Supporters of Australia's major Leftist party were, in other words, even more likely to be anti-authority than they were likely to be in favour of change. In the same study attitudes to authority also correlated very highly (.73) with a collection of radical attitudes generally. Leftists reject all authority that they do not themselves control and that rejection is a central part of their thinking.
A small 2010 update
Intelligence and knowledge are of course not the same but they are related. From memory, Factor B in the Cattell 16PF measures IQ by testing knowledge of increasingly esoteric facts.
A Feb. 2010 Pew Research Center study provides evidence that Republican voters know more about current affairs, issues and news:
Republicans, on average, answered one more question correctly than Democrats (5.9 vs. 4.9 correct). These differences are partly a reflection of the demographics of the two groups; Republicans tend to be older, well educated and male, which are characteristics associated with political and economic knowledge. Still, even when these factors are held constant, Republicans do somewhat better than Democrats on the knowledge quiz.
Among the largest gaps comes over knowledge of who leads the U.S. Senate. About half (48%) of Republicans are able to identify Reid as the current majority leader, while only a third of Democrats can name their own party’s Senate leader. More Republicans can name Reid (48%) than Steele (37%), the RNC chairman.
The one question in the survey in which Democrats slightly outperform Republicans is about the number of women now serving on the U.S. Supreme Court. Close to six-in-ten Democrats (58%) know that more than one woman serves on the high court, compared with 50% of Republicans. Though the Democratic Party is made up of more women than men, this finding does not appear driven mostly by gender. Republican men and women are about equally likely to answer this question correctly (about half each), while solid majorities of both Democratic men (60%) and women (57%) get this question right.
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