Thank Kihlstrom (2004), some clarity. I've just been reading his response to Henriques' proposals for a unified psychology, and the man talks a lot of sense. Although he's not totally dismissive of what Henriques' has to say, he thinks that psychology has, in effect, already been unified, to the extent that it's possible, by the cognitive revolution.

This is, however, being threatened by 'a centrifugal tendency' that is causing psychology 'to carve itself up into new disciplines'. Current divisions are often for political reasons, providing further support for the institutional/organisational hypothesis, rather than because these researchers are necessarily working outside psychology - although some of them are.

Essentially, though, Kihlstrom (2004) argues that psychology is the science of mental life. Psychology, like all other sciences, has connections out and crosses over, but this is its unifying core. The message is acceptance. Yes, fields cross-over, some psychologists connecting 'down' to biology, some 'up' to the social sciences. That, he says, is the way things will always be as psychology moves out to form new branches. The loose definition of psychology enables new research to have huge scope.

Some funky quotes:

"...psychology is not just something to do until the neurologist comes."

And for those of you addicted to neuroimaging studies:

"...physiology is a tool for psychology, but it is not an obligation."

Kihlstrom (2004) Unity Within Psychology, and Unity Between Science and Practice. (Abstract)
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