Etymology of the word, Greek origin: philosophy, “I like”; sophia, “wisdom”, philosophy like the “love of wisdom defines”. However, it remains to be seen which is this wisdom whose philosophy is the love. In addition, if philosophy were born in Greece, since when does exist it, in which forms did it appear and, finally, if there were philosophers and if there are still some, which are and which is their specific activity?

Such questions cannot receive an at the same time objective and neutral answer immediately. Indeed, the diversity of the philosophical doctrines and the figures of philosophers is such as one is placed in front of a dilemma. Or one provides only one answer, already patiently worked out by one or the other of these doctrines and considered a priori to contain all philosophy; in this case, the answer coherent, but will be controlled from the start to the supremacy of only one doctrines. Or one proposes a set of the various answers possible, necessarily partial, disparate and even contradictory between them; and in this case, the unit wants to be encyclopedic, but it is especially incoherent. Consequently, it is understood that professor of philosophy Jules Lachelier celebrates it could, in 1864, to inaugurate his course at the National university by this voluntarily aggressive consent: “What philosophy? I am unaware of it.”  

To be able to say what in fact philosophy is, it is initially necessary to hold for asset which philosophy is or exists in a certain manner. But the philosophical rigor prohibited to admit a priori that such author incarnates with him only the philosopher or that such doctrines represent philosophy perfectly, other than all the others. On the other hand, one can consider the assumption according to which the initial idea of philosophy did not cease causing, throughout the centuries, of research of which none arrived, in fact, to reach a perfect and final result.  

It is in the sense that, according to Kant, one should not speak about the philosophers, in the plural, but only of the philosopher, in the singular, “because this word, he said, characterizes a pure idea”, and even, so to speak, an ideal. And it is in this direction also that we can follow philosophy as the idea which gathers under the same project and which connects, in spite of their extreme diversity, the philosophers and the doctrines whose emergence constitutes what one names, wrongly or rightly, “the history of philosophy”.