 That leaves us with (4): a duration which is perceived both as present and as temporally extended. This present of experience is ‘specious’ in that, unlike the objective present (if there is such a thing — see  The metaphysics of time perception  below) it is an interval and not a durationless instant. The real or objective present must be durationless for, as Augustine argued, in an interval of any duration, there are earlier and later parts. So if any part of that interval is present, there will be another part that is past or future.