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The two-system machine

System 1 generates suggestions continuously and cannot be switched off. System 2 can check them, but checking costs effort. Watch what the controller actually does, then change its condition.

Controller

System 1

automatic · fast · always on
Impressions, intuitions, impulses
Builds coherence from whatever is activated
Resolves ambiguity silently
Biased to believe and confirm
Cannot be turned off

System 2

effortful · slow · lazy by default
Allocates attention, follows rules
Can doubt, unbelieve, overrule
Limited budget; effort is a cost
Endorses when unchallenged
Effort budget
0Endorsed unchecked
0Checked
0Overruled
Read the machine

Each chip is a System 1 suggestion arriving during triage on a live subject. Rested, System 2 checks a little under half of them. Switch to busy or depleted and the check rate collapses: the suggestions stay the same; the monitoring collapses. The first hour of a new subject under a clock is the busy state. Every overruled chip is an error that would have shipped.

Bottom line

You identify with System 2, but System 1 does most of the work, and your controller checks far less than you think, exactly when the stakes make checking matter. Label which system produced a judgment before you trust it.

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