There is no isolated 'I' — only the I of a relation

Buber's starting move is to deny that a self exists prior to relationship. There is no neutral, freestanding "I" that then decides to relate to things; rather, the self is constituted differently depending on which basic word it speaks — I-It or I-Thou. Speak one, and you become the kind of self that observes and uses; speak the other, and you become the kind of self capable of genuine meeting.

This is a sharp break from philosophical traditions that begin with an isolated thinking subject and then ask how it can know or relate to an external world. For Buber, relation comes first, ontologically, and the self that emerges depends entirely on the quality of relation being enacted in that moment.

Takeaway: who you are is not fixed in advance — it is continually shaped by the mode of relating you choose in each encounter.