I think by “conservatives” Mill meant king-and-country Tory-type conservatives. Traditionalists. Like todays paleocons and theocons and, to some lesser extent, bizcons and neocons.
OTOH, there’s much in Mill that today’s Libertarians would find unacceptable. E.g., inheritance tax, a “co-operative wage system,” and election of management by workers.
Progressivism just means you favor reform. The people who pushed for prohibition were progressive and so were the people who pushed to repeal prohibition.
The point is that whatever “liberal” meant in the 1930s is not what it means today. The study claims that people who identify themselves as liberals today are smarter than people who identify themselves as conservatives today.
The second link in the OP gets me to a page where I can access a PDF of the whole article.
The methodology in the study is pretty simple. Subjects are first questioned about their religion, political views and fidelity, and then those results are compared with results from a verbal skills test. The rest of the study is just the authors theorizing about their results.
If anything is suspect it might be the way they measured intelligence, but I don’t know enough about IQ tests to confirm that.
I tried the “Fulltext (OnlineFirst PDF)” link, but it takes me to a page saying access requires a subscription.
The guy’s hypotheses sound like pure evolutionary psychology.
I see. I guess the network in my law school dorm room is letting me access it. 
Paywalls have got. to. go.
If you have the time, would you mind copying and pasting the study’s definition of the term “liberal”? If a liberal for purposes of this study boils down to “people who checked the ‘liberal’ box as opposed to the ‘conservative’ box,” I’m going to question the intelligence of the researchers. I don’t think the term “liberal” in and of itself is subject to such a precise definition that we can know what it means when someone checks that box.
Are you suggesting that a significant number of conservatives would falsely identify themselves as liberal?
[QUOTE=study]
Liberalism
It is difficult to provide a precise definition of a whole school of political ideology like liberalism. Further, what passes as liberalism varies by place and time. The Liberal Democratic Party in the United Kingdom is middle of-the-road, while the Liberal Democratic Party in Japan is conservative. The political philosophy which originally emerged as ‘‘liberalism’’ during the Enlightenment is now called ‘‘classical liberalism’’ or ‘‘libertarianism,’’ and represents the polar opposite of what is now called ‘‘liberalism’’ in the United States (Murray 1998). In this paper I will adopt the contemporary American definition of liberalism. I provisionally define liberalism (as opposed to conservatism) as the genuine concern for the welfare of genetically unrelated others and the willingness to contribute larger proportions of private resources for the welfare of such others. In the modern political and economic context, this willingness usually translates into paying higher proportions of individual incomes in taxes toward the government and its social welfare programs.
[/quote]
Here is a quote.
Sounds like fair definition for fiduciary liberalism. Doubtlessly, some conservatives will protest the insinuation that they don’t care about the welfare of others, but if they don’t support the extra step of contributing more resources via taxes, then they shouldn’t have a problem with not being included as “liberals.”
I suspect that some conservatives would take issue with the exclusion of private charity from his analysis.
To the point of insisting supporters of private charity be classified as “liberals”? I think not.
My guess is that his brilliance was despite, and not because of his religion.
No, to defining conservatives as not caring about the welfare of others based upon an analysis that excludes private charity.
I can see a problem with the definition.
This would make those supporting Mother Theresa into liberals, which surely cannot be the intention.
Many “conservatives” would be surprised to learn that it is their relative uncaring about the welfare of others that defines them.
My guess is that in Newton’s time, there were very, very few atheists (at least in Europe).
They shouldn’t be. Why would they want to keep the status quo if they were doing badly under it? The only reason they cling to traditionalism, is because traditionally, they were much better off than everyone else, and that’s how they wanted to keep things.
Yes, I know. Ignorance was rife, back then.
Here’s an articlewhich posits that it is not a particular position that one holds as much as it is that people who depart from cultural norms have higher IQs. For example, Christians in Japan have better education than the atheists (the prevailing norm in Japan). I can easily see why, for example, a free marketeer in Cuba would likely be smarter than his/her peers, and a communist in University of Chicago would be smarter than his/her peers.