According to Giovanni Pico della Mirandola's speech Oratio de dignitate hominis, man is the most revered being standing in the middle of the creation and freely making himself to whatever he wants to become. In Pico's view, this freedom is the human dignity, from which philosophy derives its worth and significance.
The freedom of human being is its fate, or man seems to be doomed to be free. For Heidegger the human being stands within the range of truth of Being, from which it derives its significance.
Thus human freedom is being constituted by the truth of Being, which has, according to Heidegger, a sort of historical stratification called Seinsgeschichte (hi-story of Being). Heidegger's point is, that in this respect the human being was never free because of the oblivion of Being (Seinsvergessenheit).
Only by reconsidering the question of Being and its truth the human being can finally become human, and free. Heidegger's conception of human destiny is confronted with Pico's emphatic conception of human dignity and the intention is to bring Heidegger's philosophy into the dialogue with an author he never sough.
This can also possibly fill a sort of gap in Heidegger's conception of hi-story of Being.