Dual Process Theory

The two ways of processing information are often called ‘System 1’ (S1) and ‘System 2’ (S2) (though other labels have been used such as “intuition and reasoning”, “fast and slow”, “type 1 and type 2”). Roughly speaking, S1 is based on associative thinking, involves heuristics, and allows for quick decisions to be taken. S2 is based on focused thinking, involves a careful scrutiny of the alternative options to precisely assess costs and benefits, and requires time to take a decision.