There are three manifestations of the infinite for Descartes: The infinity of God, the infinitude of my will and the indefinite character of both the physical and mathematical world. This article is dedicated to the infinitude of my will, which is to say to the contribution of practical philosophy to the idea of the infinite. In the first section, we examine how man, from a disillusioned stance as to the finite, naturally aspires towards the infinite, that will of infinite being so intimate to the idea of the infinite that it signifies, de facto, an infinite will. The second section shows next how my will is infinite, notably because it bears the paradoxical signs of my will, which are positivity and incomprehensibility. Finally, in the third section, the infinitude of my will appears as the mark that God gave me made in His image. This implies that one may not confound the infinity of God and the infinitude of my will.