This world is your world: that is, the immediate experience of having this (world) is nothing other than yourself. Yet the world in its appearing, the phaneron (Peirce), has elements common to all possible experience: some Quality, some Otherness, some Mediation (Peirce: Firstness, Secondness, Thirdness).
Charles Kahn on Heraclitus:
It is true that wisdom, or the search for wisdom in sound thinking (σωφρονειν), begins with self-knowledge (XXIX); and Heraclitus went in search of himself (XXVIII). But what he found within his own psyche was a logos deep enough to be co-extensive with the universe (XXXV). So the true recognition of one’s self is a discovery not of what is private and personal but of what is ‘shared by all’: the unity of all nature which is the deep logos, the deepest structure of the self. And this unity is discovered in thinking, phronein, which is ‘common to all’ (XXXI), and common not only because for Heraclitus all things think but because it is precisely in thought, when it is in sound condition – as in the case of the dry soul – that one can embrace the structure of the whole universe.— Kahn (1979, 251-2)
Charles Peirce on the continuity of intelligence:
Whatever the philosopher thinks that every scientific intelligence must observe, will necessarily be something which he himself observes, or seems to observe. I have several times argued, at some length, that the unity of personality is in some measure illusory, that our ideas are not so entirely in the grasp of an ego as we fancy that they are, that personal identity differs rather in degree than in kind from the unity of “public opinion” and gregarious intelligence, and that there is a sort of identity of dynamic continuity in all intelligence. Accepting this opinion, a man is not radically devoid of the power of saying what every scientific intelligence must observe, if he has the power of saying what he observes himself. If he is in dynamic continuity with his whole self, he is in the same kind of continuity, albeit less intimate, with the whole range of intelligence. He can observe, in a fallible, yet genuine, observation what it is that every scientific intelligence must observe. Such observations will, however, require correction; because there is a danger of mistaking special observations about intelligences peculiarly like our own for observations that are open to every “scientific intelligence,” by which I mean an intelligence that needs to learn and can learn (provided there be anything for it to learn) from experience. I would here define experience as the resultant of the mental compulsions from the course of life; and I would define learning as the gradual approximation of representations toward a limiting definite agreement. My theory has to be that not only can man thus observe that certain phenomena are open to every scientific intelligence, but that this power inheres essentially in every scientific intelligence.— Peirce, unidentified fragment (NEM 4, ix-x)