Thinking, Fast and Slow

by Daniel Kahneman

System 1 operates automatically and quickly, with little or no effort and no sense of voluntary control.

System 2 allocates attention to the effortful mental activities that demand it, including complex computations. The operations of System 2 are often associated with the subjective experience of agency, choice, and concentration.

System 1 as effortlessly originating impressions and feelings that are the main sources of the explicit beliefs and deliberate choices of System 2.

only the slower System 2 can construct thoughts in an orderly series of steps.

attention can be moved away from an unwanted focus, primarily by focusing intently on another target.

highly diverse operations of System 2 have one feature in common: they require attention and are disrupted when attention is drawn away.

you will perform less well, or not at all, if you are not ready or if your attention is directed inappropriately.

It is the mark of effortful activities that they interfere with each other, which is why it is difficult or impossible to conduct several at once. You

You can do several things at once, but only if they are easy and undemanding.