Hume famously noted that when he introspected, he found no self, just a constantly shifting “bundle” of impressions. The self, such as it was, was at best a fleeting thing, having identity only as long as the bundle remained consistent, and losing that identity as the bundle shifted to new thoughts, feelings, and intentions.
Galen Strawson took this idea to imply that instead of a self, we have a series of selves, “pearls” on a string, as he first conceived them, each passing to the next. The self was a thing that lasted, on Strawson’s account, only for a few seconds or minutes, until its character was dissolved by the next set of impressions.
Others, like Locke and Parfit, have noted that there is a somewhat greater consistency to the self in that it draws upon the same memories and evinces the same habits, at least for a time. These, too, drift, but they last far longer than the seconds or minutes of Hume’s bundles or Strawson’s pearls.
All of these focus solely on the experiencing self. But what if we looked at the underlying hardware, as it were. If Hume and Strawson are right, then we cease to have selves when we sleep. And when we awake, we are new selves, not at all the selves that went to sleep.
But imagine working on a computer. You have a paper in progress, you’re keeping a few browser windows open, there’s a game in another window, and the hard drive is full of all your previous works. When you put the computer to sleep for the night, it ceases to be actively attending to any of these tasks, but they’re ready and waiting when the computer is roused in the morning.
Similarly, our brains hold much of our mental life in place. Certainly not with the precision (and parsimony) of the computer, but when we go into sleep mode, while some active processes are lost or start to degrade, much remains for when we restart in the morning. And if we think of the self not merely as the experiencing self, the passing show or bundle, but as the entire organism of subjective potential, contained, at least largely or in important ways in the matter of the brain, then there is a self across time. And, though it isn’t doing much while we sleep (at least during dreamless sleep), that doesn’t mean it doesn’t exist. It’s there, just as our computer’s memory state and capacities are there, waiting to be woken.
Perhaps a non-active self makes no sense, perhaps that’s not what “self” means. But if by “self” we only mean “self-experience,” there must be still be some self to be experienced, and it seems profitable to think of it as a thing that can sometimes be doing nothing. We don’t think of other things as vanishing when inactive; perhaps the self is best thought of as simply quiescient, rather than gone, when it is not in service. And if that’s the case, then the “bundle” is merely some activity of the self, and not the self itself. The self could be both the active content of consciousness, and our storehouse of ideas and memories, and our capacities to act upon them, all of which have a persistence across time that some fleeting action only gives a glimpse of.
Just to clarify a little, I’m arguing (against readings like that of Hume, G. Strawson, and Pali Buddhists) that continuity of consciousness is not (necessarily) necessary for sameness of self. That is, even if there is a disruption in the flow of consciousness (e.g., sleep, a sudden change of attention) that doesn’t mean that the being that follows isn’t properly continuous, as self, with the being that went to sleep or changed its occurrent conscious contents. Self might best be understood in terms of the “bundle of impressions” or conscious content, but that content is _stored_ and is relevantly the same content when we access it later. The model of the computer is merely meant to illustrate a way this could be understood; I’m not claiming that self is reducible to or perfectly analogous to a computer. Rather, that they are relevantly similar in that both have active modes of their content, as when it is in RAM, and, let’s say, storage modes, as when it is on the drive awaiting access.