I wish that someone would do a real analytical piece on the psychological origins of liberalism.
You might try reading Paul Johnson's "Intellectuals", and Horowitz's "Politics of Bad Faith", for at least an attempt at some insight into the psychology of Lieberals.
I doubt if any actual psychologist would attempt it, though - that would involve admitting that Lieberalism is a psychological "condition" of some sort, rather than just a "normal" state of mind - which would in turn require (a) some objectivity, and (b) introspection, on the part of the psychologist, since he/she/it would in 99% of cases already be a doctrinaire Lieberal. (They've attempted plenty of analyses of "conservatives", though, of curse...)
An oversimplified (but maybe not much) assessment claims that Lieberals are basically overgrown children who can't cope with life, are usually mad at the world, and are alternately either trying to get their surrogate Mommy/Daddy the Government to take care of them, or rebelling against it as the manifestation of a parental authority figure...