[How about this metaphor?
The person’s psyche is like a steam engine.
Perhaps, the normal contexts of think and law act like regulators. Conscience and dispositions act like fuel.
Sigmund Freud, one of the founders of psychoanalysis, started with a picture of the unconscious as a steam engine powering a locomotive.
Freud wrote between 1890 and 1950 AD (7690-7750 U0′).]