This article shows how the thoughts of Parmenides and Heraclitus are in syntony with each other, inasmuch as both condemn the illusory character of usual understanding, always blind to that which, seemingly invisible, leads them to investigate about nature (perì phýseos). We usually we do not see what Parmenides sees, that is, that the truth is that there is only being and that, absolutely, there is not non-being. We do not realize that all we somehow name non-being already is and, thus, non-being is only an illusion. We do not understand that once the totality of being is only that which is, being always now - not this or that determined now - it is necessarily motionless because it embraces everything. Neither do we see what Heraclitus points out, that is, that the truth is that there is only one and the same, always dynamic conjuncture in the game of opposites, an originary war, and that the usual perception of individual beings, isolated in relation to each other, is, also, illusory. We only see each thing in its isolated individuality, as if each one could be some finished and fixed thing. These two thinkers operate on the intelligibility level of principles as such, beyond the immediate understanding of ordinary men. Even if the perspectives vary from which each one names that which remains invisible to the non philosopher, both assert the unity and sameness in and of the principle.
Physis; nature; Parmenides; Heraclitus