Starting from a critique of the famous Gentile thesis that philosophy cannot «give itself» except in its history and that it «cannot be divided into separate or separable parts», the essay analyzes the weight that this conception of philosophy has had on Italian philosophical historiography. «Doing philosophy», including the models of Eugenio Garin (philosophy as historical knowledge), Paolo Rossi and Delio Cantimori who also criticized the actualistic and metaphysical presuppositions, signifies do it as Gentile did. Philosophy in Italy has been and still is learned today, for the most part, still «only in its history». The example of the manuals adopted in teaching philosophical discipline in upper secondary schools in Italy is eloquent. To go beyond this model, which still retains its great historical and philological merits (analyzed here), we propose an example of doing philosophy (and teaching it) as a history of problems, starting from the problems and philosophical themes of the present. In this sense, a key notion of Western thought is analyzed, the problematic notion of «Nature», faced from multiple points of view: from the theme of the so-called «Human Nature» linked to Greek physis, to the hendiadys of nature/culture, and finally, the connection between human nature and political power. It is a new model of «Doing philosophy» that attempts to keep the philological achievements of the Garnian and Gentilian lessons, in order to overcome them, in view of a new critical philosophical thought at the beginning of the 21st century.