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A brute kills for pleasure. A fool kills from hate.
— Robert Heinlein · Time Enough for Love
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The two sentences condemn killing through a contrast between motives. Pleasure earns the name 'brute'; hatred earns the name 'fool'. Their matching structure makes the judgment sharp and memorable, assigning a different failure to each motive without excusing either one.
Context reviewed