According to Buddhism mind is nothing but a complex compound of fleeting mental states. Immediately after the cessation stage of a thought moment there occurs the genesis stage of the subsequent thought-moment. Every fresh consciousness consists of the potentialities of its predecessors together with something more. There is therefore, a continuous flow of consciousness like a stream without any interruption. Here there is no identical being but there is an identity in process.
Every moment there is birth, every moment there is death.
In the course of one life-time there is momentary rebirth without a soul. It must not be understood that a consciousness is chopped up in bits and joined together like a train or a chain. The rapidity of the flow is such that hardly is there any standard whereby it can be measured even approximately. Here we find a juxtaposition of such fleeting mental states of consciousness opposed to a superposition of such states as some appear to believe. No state once gone ever recurs nor is identical with what goes before.