Kant has never written a History work. Nevertheless it is precisely with him that History becomes a philosophical problem, that is, it is covered by a selfdignity and becomes part of the critical system. At inquiring the knowledge principles, Kant imposes new criteria to the thought of human action concerned to time, to the possibility of knowing and to the subject. The relation among pastpresent- future is shaken up from the inside conceding to History a temporality of its own in relation to religion and politics. The knowledge about History is assumed as long as it can be experienced, becoming thus its own knowledge. With Kant, humanity is raised to the condition of subject of History, what, in one hand, reduces the man s action field and, in the other, extends his responsibility. The debate concerning the human nature and the moral autonomy guides the critical system and crosses throughout this Idea. On this dialectics, Kant establishes an ethical formal horizon leading men s action and thought on an endless task. As critical reason, it is necessary that the thought always work against itself making, in this manner, the present the starting and arrival point to History.