IMHO, it's a metaphor; it's good, and very convenient because our understanding of how the brain actually works has been (and still is) limited.

Take a look at the Latin root pro / cras / crastinus / procrastinare / procrastinat and in the late 1500s, voila, English procrastinate. It means "deferred until the morning, or deferred until tomorrow".

Why do we defer tasks until tomorrow, and tomorrow, and...? Is it not usually avoidance behavior? I procrastinate cleaning up the basement because it is boring, tedious, carries few intrinsic rewards (few? More like zero.). Tomorrow, maybe. It's not "inertia", it's strategy--avoiding or delaying unpleasantness.

We use computer metaphors for the functioning of the brain. It's a computer. There are circuits. There is programming, deprograming, and reprogramming. There are viral thoughts. There are inputs, and so on. We use mechanical metaphors too: power, drive, bandwidth, overload, etc.

:point: :ok:

Also, wasn't it the other way round, to some extent? Weren't Newton & co. rather cheekily re-purposing psychological words like force ("courage, fortitude"), inertia ("unskillfulness, ignorance"), moment ("importance")? (Cherry-picked from Online Etymology Dictionary.)

Good observation.

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