  At the heart of Husserl’s account is a dynamic tri-partite view of the composition of consciousness at any instant. The three components are: primal impressions, retentions (or ‘primary memories’) and protentions. Primal impressions are the live, actual experiences that occupy the momentary now. No sooner does a primal impression – e.g., a momentary tone-phase – occur than it slips seamlessly into the past. But it does not vanish from consciousness altogether: it survives in the form of a retention, which presents it as past. For Husserl, retentions are a quite distinctive form of consciousness, and differ significantly from ordinary memories. (They are also the ‘adumbrations’ mentioned in the quotation.) As new primal impressions dawn – as they gush forth from the ‘primal source-point’ of the now – the initial tone-phase continues to be retained, but as increasingly more past, until it fades from consciousness altogether. From then on, it can only be accessed through ordinary memory. As for protentions, these are the future-oriented counterparts of retentions. In some cases – e.g., when we are perceiving or remembering a familiar sequence of events – they can be quite detailed, but often they consist of nothing more than an openness to the future, an expectation that something will come. Or as Husserl puts it: