I describe in this article the arguments that Blackburn put in dispute between Achilles and the turtle regarding the reasons that motivate human actions. For they sign sharply Humean positions, the ideas of the turtle are not framed perfectly in none of the polarizing currents of the contemporary philosophy regarding the theme, although close to neo-Humean pole. In this way, the so called ";Humean challenge";, that throws to the proponent of categorical reasons the onus to argue for their existence, become worsened by the return to the Hume original position that there are no reasons, be them hypothetical or categorical, that could move human being, just passions.
