the.com/behaviour

What you do when a mood, an incentive, and a habit gang up on you.

means The way a person or thing acts, especially the observable pattern of what they do rather than what they claim or feel.

from From Middle English 'behaven,' built from 'be-' plus 'have' — in older English 'have' could mean 'to hold or comport oneself,' so to 'behave' was literally to 'have yourself' in a particular way. The noun picked up its extra 'u' (behaviour vs. behavior) through the same British-vs-American spelling split that gives us colour/color and honour/honor, both descending from French spelling habits layered onto English roots.

spelling split
british u, american drops it, same chaos
root
old english havian, meaning to have oneself
science angle
behaviourism tried to study only actions, not minds
honest truth
easier to change than beliefs, harder than promises
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