Patanjali's yoga sutras

क्रमान्यत्वं परिणामान्यत्वे हेतुः॥१५॥

3.15 kramānyatvaṁ parināmānyateve hetuh

krama = succession

anyatvam = distinct

parināma = transition

anyatve = distinctness

hetuh = reason

When you reason that there is an aspect of consciousness distinct from this succession of identities, this is the transition to distinctness. Your awareness expands to hold this distinct consciousness within it.