Dennett vs. Egan, different horror levels, same ideas

28 Dec, 2023

Dan Dennett is a philosopher best known for his writing about consciousness. To a first approximation you could call him a materialist. His long-term project has been to show that the perplexing features of conscious experience can be located within the order of nature, without requiring radical new metaphysics (or physics). Once we understand consciousness well enough, we see that we are not required to say anything wacky like, "All matter is conscious." Hence critics have lampooned his fantastic book Consciousness Explained (1995) as, "Consciousness explained away."

Greg Egan is a science fiction writer in the "hard sci-fi" tradition, meaning that his fiction is built on the rigorous working out of suppositional premises about how things work. Often (perhaps usually) his premises relate in some way to how the mind works. The premises are often both conceptually ingenious and very plausible. That is, they have the character of strong conjectures about the way things actually work in the real world. In formulating this last kind of premise, the work of the philosopher and the science fiction writer can overlap very closely. Readers of both Dennett and Egan will have noticed that their premises have coincided more than once.

Two of my favorite Dennett pieces have close matches in Egan's fiction. Dennett's "Where Am I?" (1978) is a brilliant short piece that in fact takes the form of a science-fictional vignette. (It can be read here. A very successful friend has told me it caused her to switch her degree from linguistics to philosophy. It had a similar if less dramatic effect on me.) I will slightly spoil the story by giving my gloss on the main argument (although as we will also see there's more to unpack). The argument is that the embeddedness of consciousness in space -- the answer to the question "Where am I?" -- is a question about the representative contents of conscious experience, rather than about its external metaphysical status.¹ In the leading example, "I" am not "in" "my" head because the information-processing that determines my consciousness occurs inside my head, but because I experience myself as being in my head. Because of this, the question, "Where am I?", may sometimes be an empty question, one with no single determinate answer. (A theme of Dennett is to turn apparently sharp-edged metaphysical questions into matters of interpretation and of degree.)

I slightly spoil both pieces by pointing out that "Where Am I?" and Egan's "Learning to Be Me" (1990; available in his Axiomatic and Best Of) share an argument. The twist introduced at the end of Dennett's piece is the central tension and then twist ending of Egan's (although the issue of spatial embeddedness plays a lesser role in the latter). Here, we could say, Dennett has scooped Egan (although do read Egan's story, which is very elegant and horrifying; I'll return to the latter point).

The second Dennett piece is "Time and the Observer" (1992; reprinted as Chapter 5 in Consciousness Explained). In this excellent piece, Dennett argues that the embeddedness of consciousness in time is also a question about the representative contents of conscious experience, rather than about its external metaphysical status.² In particular, the timing and temporal order of experience is not in any simple correspondence to the timing and temporal order of the underlying physical events that constitute, subserve, or produce that experience. I think it probably takes more to explain this argument but I'm going to leave it at that for the moment. Instead I'll introduce Egan's treatment, first in his short story "Dust" (1990) and then in his amazing novel Permutation City (1995). Egan dramatizes the point that Dennett will later make using the device of simulated consciousnesses. He has the character, Paul, run a series of computer simulations of himself, with the simulations being run in different temporal orders on the computer -- forward, backward, scrambled up, etc. But in all cases the temporal experience of the simulated Paul is the same -- that is, forward. This is, I think, clearly what the result of the experiment has to be. If we assume that the Paul simulation works at all -- that is, that it realizes a conscious experience -- then the same deterministic execution trace of the simulation has got to yield the same experience, whether it is run quickly or slowly or even out of order or backwards. This, anyway, is Egan's perspective (both in the story and ex cathedra), and it's also what Dennett argues for (in the much more challenging context of the physical brain) in "Time and the Observer."

This time, then, Dennett in a way got scooped by Egan (1990 vs. 1992). In a larger sense, though, maybe the whole thing is already implicit in "Where Am I?", since, if I am right, the later piece is essentially transposing the argument of the earlier from space into time. In an even larger sense, maybe the whole thing is already implicit in Kant's Critique of Pure Reason (based on an oblique remark of Dennett's I think maybe he thinks this; and maybe I do too). Anyway, the point is not to gin up any priority dispute³ but just to note the connections between two very insightful writers. And to draw one contrast.

The contrast is this: Egan's stories are horror stories, self-consciously so. "Learning To Be Me" is chilling to read and haunting to think about. The same material in Dennett's hands is mostly comedic, even when he is drawing the same implications that Egan renders as horror. Similarly, "Dust" and Permutation City are at least a bit disturbing. They dramatize how their perspective destabilizes our understanding of our place in the world. If their ideas are right, then much of what we value and rely on may be deeply mistaken. I think there are smart people online who are genuinely worried about the possibility that the "dust theory" is true (I sort of am worried cuz I think it's true, but I have basically decided how to live with it).

Unlike Egan, Dennett does not play up the horror of his arguments. In general, I think, he tries to protect things like ethics and the meaning of life from the potentially revisionary consequences of his metaphysical interventions. For example, he argues that "free will worth wanting" is compatible with metaphysical determinism. Don't let the metaphysics disturb you, see, because what was really important in your life only seemed to depend on what has been revealed as metaphysically dubious. But if Dennett and Egan are developing the same material, and it is horrifying in Egan's hands, you have to wonder if Dennett is doing it justice. More generally, I think it is important to Dennett that a disenchanted view of the world is still a friendly one, with room for all the warmths that make life worth living. But whether this is true is ultimately an open question that, if it matters to us, we have to face directly.