In L'Action, Blondel developed a "philosophy of action" in which he applies the method of phenomenology. This leads him to the first order issue of "action", critiquing the Enlightenment enshrinement of thought, which he subsumes under the category of action. This leads him to discover the distinction between the willing will and the willed will. This distinction shows a real insufficiency between the two elements of the will. The problem of connaturility - that man cannot desire something which cannot be fulfilled - leads to investigating how the willing will can be fulfilled in the willed will. This insufficiency leads him to eventually hypothesize the supernatural as the only real possibility. He insists that this is as far as a philosopher can go, that the supernatural is the real end of man, and that the content of the supernatural is left to the realm of theology.

(Source: Wikipedia)