Ce livre propose une nouvelle interpretation du Timee de Platon dans laquelle le mythe cosmologique est identifie a une experience de pensee. Le discours de Timee nous demande ce que nous ferions si nous etions un artisan divin charge de faconner l'univers en conferant de l'ordre a un milieu chaotique. Apres avoir adopte trois criteres a satisfaire pour appartenir a la categorie de l'experience de pensee (1 : contrefactualite ; 2 : necessite de la production d'images ; 3 : progres cognitif), il est defendu que le discours de Timee contient a la fois une sequence d'arguments deductifs et la possibilite de combiner ces arguments en differents modeles mentaux de l'univers. This book offers a new interpretation of Plato's Timaeus in which the cosmological myth is identified with a thought experiment. Timaeus' discourse asks us what we would do if we were a divine craftsman in charge of fashioning the universe by bestowing order upon a chaotic milieu. After having adopted three criteria to be satisfied to belong to the category of thought experiment (1: counterfactuality; 2: necessity of image productions; 3: cognitive progress), it is defended that Timaeus' speech contains both a sequence of deductive arguments and the possibility to combine these arguments into different mental models of the universe.