Jonathan Haidt is a prominent social psychologist.

From his Wikipedia entry (Jonathan Haidt) :

Haidt has been named one of the “top global thinkers” by Foreign Policy magazine, and one of the “top world thinkers” by Prospect magazine. In fact, he is among the most cited researchers in political psychology and moral psychology, and has given four TED talks.

More information about different projects he is involved in can be found on Jonathan Haidt’s home page at NYU: Jonathan Haidt’s Home Page

The work Dr. Haidt did accurately reflects some of the psychological differences between liberals and conservatives.  He breaks morality down into 5 foundations and then shows how liberals and conservatives are alike and how they differ.

These are quotes from the transcript of his TED talk: The Moral Roots of Liberals and Conservatives

1. harm/care. We’re all mammals here, we all have a lot of neural and hormonal programming that makes us really bond with others, care for others, feel compassion for others, especially the weak and vulnerable. It gives us very strong feelings about those who cause harm.

2. fairness/reciprocity. There’s actually ambiguous evidence as to whether you find reciprocity in other animals, but the evidence for people could not be clearer. This Norman Rockwell painting is called “The Golden Rule” — as we heard from Karen Armstrong, it’s the foundation of many religions.

3. in-group/loyalty. You do find cooperative groups in the animal kingdom, but these groups are always either very small or they’re all siblings. It’s only among humans that you find very large groups of people who are able to cooperate and join together into groups, but in this case, groups that are united to fight other groups. This probably comes from our long history of tribal living, of tribal psychology. And this tribal psychology is so deeply pleasurable that even when we don’t have tribes, we go ahead and make them, because it’s fun.

   Sports is to war as pornography is to sex. We get to exercise some ancient drives.

4. authority/respect. Here you see submissive gestures from two members of very closely related species. But authority in humans is not so closely based on power and brutality as it is in other primates. It’s based on more voluntary deference and even elements of love, at times.

5. purity/sanctity. Purity is not just about suppressing female sexuality. It’s about any kind of ideology, any kind of idea that tells you that you can attain virtue by controlling what you do with your body and what you put into your body. And while the political right may moralize sex much more, the political left is doing a lot of it with food. Food is becoming extremely moralized nowadays. A lot of it is ideas about purity, about what you’re willing to touch or put into your body.

Of those 5 foundations, two are universal to both conservatives and liberals: harm/care and fairness/reciprocity. The difference between liberals and conservatives lies in the other three foundations: in-group/loyalty, authority/respect, purity/sanctity

Moral conservatives rate highly on all three, and for moral liberals they almost don’t exist.

So liberals end up with a two channel moral code:

• harm/care
• fairness/reciprocity

Conservatives end up with five channels:

• harm/care
• fairness/reciprocity
• in-group/loyalty
• authority/respect
• purity/sanctity

The TED talk Dr. Haidt gave on this information is about 20 minutes long.  For me, it was eye opening.  If you want details about what exactly these foundations mean and how they affect people in real life, please watch the TED talk: The Moral Roots of Liberals and Conservatives.