On the Dignity of Man in Kant

The contribution starts with the observation that Kant mentioned Human Dignity in his main works with great variety in emphasis. In the ‘Grundlegung’ from 1785 we find a significant treatment and again in the ‘Tugendlehre’ from 1798 but none in the ‘Kritik der Praktischen Vernunft’ from 1788 and in the ‘Rechtslehre’ from 1797. This needs an explanation. In the ‘Grundlegung’ human dignity is not attached to the second formula of the categorical imperative, the formula of self-purposefulness, as it is often assumed, but to the third formula of a kingdom of ends. It is there explained as self-legislation. This placement needs also an explanation, which is attempted by the article. In the ‘Tugendlehre’ human dignity is then explained as self-purposefulness. So Kant changed his understanding of human dignity from the ‘Grundlegung’ to the ‘Tugendlehre’. But the question is: why?