“It is an old truth of Marxism that every human activity should be judged according to the objective meaning in the total context, and not according to what the agent believes the importance of his activity to be.”
Georg Lukács, “Realism in the Balance” (1938) (reprinted in Aesthetics and Politics)
Note also Lucius Cassius’ legal principle, recorded by Cicero in Pro Roscio Amerino, “Cui bono?”.
For the exact opposite position, see The Fountainhead