The principle gives You On AI's central question — 'are you worth amplifying?' — its specifically existentialist weight. Read through Sartre's framework, the question is not about potential. It does not ask what you could produce if conditions were right. It asks what you have produced — what you have chosen to build, for whom, and at what cost. The amplifier does not amplify intentions; it amplifies actions. And the actions are the person.
The builder who uses AI to produce more output has not become more productive in any deep sense. She has produced more. The production is her. If the production is careless — code ships without understanding, products launch without consideration of who they serve and who they harm, output multiplies without the judgment that determines whether the output deserves to exist — the carelessness is not a deficiency of deployment. It is a fact about the person. She chose to produce carelessly, and the choice defines her.
The pace of this self-constitution has accelerated in ways Sartre could not have anticipated but would have recognized. The builder using AI is not choosing once who to be; she is choosing a hundred times a day, in each prompt, each accepted or rejected output, each product shipped or shelved. The accumulation of micro-choices constitutes her fundamental project at a speed that compresses what used to be a career-long process of self-creation into months. The responsibility does not scale down with the speed. It scales up.
The principle appears in Existentialism Is a Humanism (1946) as the ethical summary of the existence-precedes-essence thesis, and is developed throughout Sartre's biographical studies where specific lives are read as constituted by the choices they made. The AI-age application is the Sartre simulation's extension to the conditions of amplified action.
Action constitutes identity. Who you are is nothing other than the pattern of what you have actually done.
Intentions do not count. The person who intends compassion but never acts compassionately is not compassionate.
The amplifier carries the signal of action. What AI amplifies is not your potential or your good wishes but your actual choices and their consequences.
Universalizing dimension. Every choice implicitly claims this is how a human being should act in this situation — the chooser creates, through her choices, an image of the human being as she thinks it ought to be.
The principle has been criticized for leaving no room for moral growth — if you are your actions, what about the person who has acted badly but is trying to change? Sartre's reply is that the attempt to change is itself an action, and the person who authentically undertakes the work of change is, through that work, becoming a different person. Identity is never finished; the pattern of actions continues to constitute the person until the person stops acting.