Full Idea
A person's desires and beliefs tend to cause what they tend to rationalise. This coordination of causality and rationalisation lies at the heart of psychology.
Clarification
'Causality' is the process by which things actually happen, rather than statically existing
Gist of Idea
Psychology studies the way rationality links desires and beliefs to causality
Source
Gabriel M.A. Segal (A Slim Book about Narrow Content [2000], 5.3)
Book Reference
Segal,Gabriel M.A.: 'A Slim Book about Narrow Content' [MIT 2000], p.150