We all have experiences as of physical things, and it is possible to interpret these experiences as perceptions of objects and events belonging to a single universe. In Leibniz’s famous image, our experiences are like a collection of different perspective drawings of the same landscape. They are, as we might say, worldlike.
Ordinarily, we refer the worldlike quality of our experiences to the fact that we all inhabit the same world, encounter objects in a common space, and witness events in a common time.
J.S. Mill thought that we should abandon this way of thinking. According to Mill, the world is a collection of “permanent possibilities of sensation”–fundamental propensities for conscious experiences to occur in certain patterns rather than others (or in no pattern at all). The physical world that we perceive doesn’t explain the worldlike quality of our experiences: it is the worldlike quality of our experiences, or rather it is the tendency for experiences to constitute a worldlike totality of the sort that our experiences do, in fact, constitute. This proposal has come to be known as “phenomenalism.”
The phenomenalist sees the physical world as an all-encompassing hypertext. The cantaloupe on the table is not an independently-given thing-in-itself that lies behind my visual experiences of it. The cantaloupe is a network of phenomenological hyperlinks. Click for visual sensations of something round and beige. Click again for tactile sensations of something cold and rough. With luck, the next click will take you to flavor sensations of something sweet and juicy.
The hypertext analogy must be handled with care. In an actual hypertext (like the one you’re reading now), the links are grounded in some underlying computer hardware: take away that underlying hardware, and you take away the hypertext. In the phenomenalist’s world, the only thing that underlies a hyperlink is more hyperlinks. The computer hardware is itself nothing but a system of hyperlinks. It’s hyperlinks all way down.
Another potentially misleading feature of the hypertext analogy is that the navigator of an actual hypertext (like you) is not part of the hypertext that he or she navigates. But when a phenomenalist says that the world is an all-encompassing hypertext, he means it. Not only is the melon a network of phenomenological hyperlinks: so is the refrigerator that chills the melon, the knife that cuts the melon in half, the hand that holds the knife, and the mind that guides the hand. A cantaloupe is a tendency for conscious experiences to occur in one sort of pattern; a mind is a tendency for conscious experiences to occur in a different sort of pattern.
Because phenomenalism has never been very popular, the theory hasn’t really evolved since Mill introduced it to the world in 1865. One significant development during the intervening 150 years was a revolution in our understanding of time. Time, it turns out, is not an independent dimension, but merely an aspect of relativistic spacetime. And in relativistic spacetime, there is no way for things to relate temporally without also relating spatially.
This has important implications for phenomenalism. A physical object, on Mill’s view, is a tendency for conscious experiences to occur in certain temporal sequences rather than others. This makes sense only on the assumption that conscious experiences occur in time, which, in a relativistic context, makes sense only if the experiences also occur in space.
But if conscious experiences are in space as well as time, physical things start to look more like geometrical than logical constructions of experiences (assuming that they are experiential constructs at all). Mill’s position devolves into a panpsychism that differs from common materialism mainly in its attribution of sentience to fundamental particles.
To avoid this slide into panpsychism, a phenomenalist has only one choice. He has to take consciousness out of time.
Now, most people, including Mill, think it is beyond obvious that experiences occur in, extend through, and change over time. To them, the suggestion that consciousness might not be in time is not just wrong, but unintelligible.
But is it?
“The natural world is far less mysterious to us than it was just a few centuries ago—except for that bit of it called ‘consciousness.'”
When I gaze at the full Moon, I have an experience as of something round and enduring: my experience has the qualities of phenomenal roundness and phenomenal duration. From the fact that the experience is phenomenally round, I don’t infer that it is literally round (like the Moon itself). So why should I infer from the fact that the experience has the property of phenomenal duration that the experience literally endures? Why should the evidence of introspection lead me to infer that my experiences have any objective temporal features at all?
Once we see that there’s no incoherence in the idea that consciousness transcends time, an intriguing possibility comes into view: the possibility that consciousness might serve as a suitable basis for the metaphysical reduction of temporal phenomena, including time (or spacetime) itself.
Phenomenalism can easily seem out of touch with modern ways of thinking. The natural world is far less mysterious to us than it was just a few centuries ago—except for that bit of it called “consciousness.” Putting consciousness at the foundation of our metaphysics can easily look like trying to explain the well-understood in terms of the poorly-understood.
But sometimes the best thing to do with something that resists explanation is to cast it in the role of unexplained explainer. (The evolution of scientific thinking about gravitation is a good case in point.) That is the role that Mill envisioned for consciousness in relation to the physical world.
Is philosophy ready to take phenomenalism seriously? I don’t know. It depends on how willing we are to step back and survey the field of metaphysical possibilities as if for the first time. “Common sense,” writes Russell, “leaves us completely in the dark as to the true intrinsic nature of physical objects, and if there were good reason to regard them as mental, we could not legitimately reject this opinion merely because it strikes us as strange. The truth about physical objects must be strange.” Phenomenalism might be that strange truth.