St. Augustine suggested that when we try to grasp the idea of time, it seems to evade us: "What then is time? If no one asks me, I know what it is. If I wish to explain it to him who asks, I do not know." So is time real or merely an artificial construct? Is time a fundamental or emergent property of our universe or a part of our cognitive apparatus? Do we live in a continuum with a definite past and present, or do we live in a succession of ‘Nows’, and if the latter is the case, how does it affect our perception of memory or recollection?