In one of the final chapters of his book: Reality+: Virtual Worlds and the Problems of Philosophy, David Chalmers asks, have we fallen from the Garden of Eden? “Eden” in this case is a metaphor for living in a world where everything is as it seems, matching our pre-theoretical view of reality.
In Eden, everything exists in a three dimensional Euclidean space. And time flows from one moment to the next with an absolute now across all of space. In Eden, color is an intrinsic property of objects, so the apple really is red. And objects like rocks are truly solid. In Eden, we have free will in the classic contra-causal sense of that term.
Once we lived in Eden. But then there was a fall. We ate of the Tree of Science and were cast out.
We discovered that we actually live in four dimensional spacetime as described by general relativity, where space can be warped by matter and energy, and the passage of time varies by velocity and gravity. Color turns out to be complex dynamics involving how our nervous system uses the wavelength of reflected light to reach categorizing conclusions about observed phenomena. Solidity depends on how elementary particles interact. And most scientists and philosophers have written off libertarian free will.
Philosopher Wilfred Sellars referred to the Edenic view as the “manifest image”, and the post-fall one as the “scientific image”. Of course, we can take the manifest or the scientific view for just about any thing or concept, including the sun, trees, people, etc. But the views often clash, and their reconciliation often isn’t obvious. Which raises the question of what to do when they disagree.
Chalmers lists four possible strategies.
- Elimination: Abandon the manifest image in favor of the scientific one, as we once abandoned concepts like ghosts and witches.
- Identification: Establish how the manifest image relates to the scientific one, such as understanding that water is H2O.
- Autonomy: Keep the manifest image even when it doesn’t appear to match up with any scientific concept.
- Reconstruction: Alter the manifest image to make it compatible with the scientific one.
Chalmers notes that there’s no single universal answer for every concept. Sometimes our manifest image is counter-productive and just needs to be eliminated. But if it remains useful in everyday life, then an argument can be made for trying to identify it with a scientific concept. Some philosophers seem to find autonomy a good option for consciousness or free will, although I personally think we should only accept this strategy as a temporary stop-gap, until we can figure out which of the other strategies is appropriate.
But Chalmers identifies the fourth, reconstruction, as the most important. With this option, we acknowledge that the concept remains useful, but also that it isn’t what we naively thought it was.
Typically reconstruction involves a move from primitivism about the concept to functionalism.
For example, the Edenic view of solidity is as a primal intrinsic property of an object. But objects are composed of elementary particles that interact in various ways, sometimes attracting, other time repelling each other, and some particles, such as neutrinos, pass right through other matter, only rarely interacting with it. (Dark matter may not interact at all, except gravitationally.) Once we understand this, we might be tempted to eliminate the concept of solidity. But solidity is too useful in everyday life.
Instead, it’s better to reconceptualize solidity, not as something intrinsic, but as something matter in certain configurations does. Solidity is about resisting penetration, about how matter interacts with other matter, at least of certain types. In other words, solidity is a role, a function, the function of resisting penetration. Solidity is as solidity does.
Along these lines, colors moves from an intrinsic property of objects to a reaction of our nervous system that allows it to reach associational conclusions about those objects. Color is as color does.
And space becomes that which mediates motion and interaction. Space is as space does. (Chalmers notes that space remains fundamental in general relativity, but is increasingly called into question in some quantum theories, as something that may be emergent from entanglement and/or a higher dimensional reality. Understanding that emergence might be easier if we remember that the emergent phenomena only needs to provide the role of space.)
Tying this back to the subject of the book, functionalism shows how objects in a virtual reality can have color, solidity, and be in space, in the same sense of the role of these concepts in non-virtual reality. Of course, if we’re in a simulation, then that might already be what we’re dealing with, and things are not as they seem. But Chalmers’ point is that even if we’re not in a simulation, things seem like Eden, but aren’t. So we could view Eden itself as a type of simulation, just one constructed by our nervous system.
Chalmers points out that the Edenic version of reality is epistemically fragile. Clinging to it results in a model of the world that appears particularly vulnerable to Cartesian skepticism. It can lead to philosophies like those of Donald Hoffman, who sees reality as an illusion. But taking a functional view results in a more robust model, one more resilient to this type of skepticism. Reality is as reality does.
Put another way, the reality-illusionists are right to dismiss a naive realism claiming things are what they seem. But functionalism gives us options other than illusionism, resulting in a sort of “imperfect realism”. It’s worth noting that this is really just another description of structural realism, with the functionality arising from a system’s causal structure and its relations with the environment.
Of course, this is Chalmers, so he makes one exception to this universal functionalism: consciousness. Everything else can be addressed by structure and relations, but he sees consciousness as uniquely and stubbornly resistant to that move. To be fair, his views here are nuanced, in that he allows there may be some differences between the manifest and scientific image of consciousness. But I think clinging to even a semi-Edenic notion of consciousness comes with the same vulnerability noted above. Like everything else, a functional view of consciousness is more resilient. Arguably, consciousness also is as consciousness does.
What do you think? Which strategy would you favor for reconciling the manifest and scientific images? Is reconstruction, as Chalmers asserts, the best one? Does this take on functionalism make sense? If not, what are its flaws?