2. The Argument from Psychophysical Harmony for Theism
2.1 Psychophysical harmony
Here we present the argument from psychophysical harmony in its basic
form. We’ll initially make some substantive assumptions about the
metaphysics of consciousness. In §3, we show that the assumptions can
be relaxed without seriously affecting the argument. The assumptions
are:
- Dualism: Phenomenal truths and physical truths are distinct and co-fundamental, with neither class of truths grounded in the other.
Physical and phenomenal states are linked by metaphysically contingent
fundamental laws of nature that specify which physical configurations
give rise to consciousness in its various forms.
- Causal completeness: Every physical event involved in human behavior and brain functioning has a sufficient causal explanation in
terms of prior physical occurrences.
Together, these assumptions imply the disjunction of epiphenomenalist
and overdeterminationist dualism.
Given dualism, we think that the very existence of consciousness is at
least some evidence for theism. If consciousness is ontologically
distinct from any physical properties, a physical universe can host
consciousness only by adding it to its supply of fundamental features.
That it would do so is unsurprising if our universe was designed by a
being which aims to realize value. A world with intricate arrangements
of matter but no experience is clearly missing some important kinds of
value, and perhaps missing value altogether. It’s far more surprising
that consciousness should exist (and that there should be fundamental
laws governing its occurrence) if the universe is not ordered in any
way toward the realization of value. There would be no reason to
expect it to exist, and the fundamental laws would be simpler if it
didn’t. (By contrast, that mass or charge--properties without apparent
normative significance--are included among the universe’s basic
features doesn’t seem much more surprising on atheism than theism.)
However, the main focus of our argument will be a different set of
facts about consciousness, which we’ll call the facts of
“psychophysical harmony”:
Psychophysical Harmony: States of consciousness are related to each other, and to physical states, in strikingly harmonious ways—ways
that seem extremely lucky, or involve many striking apparent
coincidences.
Various instances of psychophysical harmony have been emphasized in
recent work by Adam Pautz (2020), David Chalmers (2018), Philip Goff
(2018), Hedda Hassel Mørch (2017, 2020), Harold Langsam (2011), Noa
Latham (2000), and Bradford Saad (2019). We’ll discuss two main types
of harmony: normative harmony and semantic harmony.
2.2. Normative harmony
Many examples of psychophysical harmony are cases of what Adam Pautz (2020: 5) calls
normative harmony, which he defines as follows:
Normative harmony: In every case, the psychophysical laws correlate a physical functional state P with a distinct conscious
experience C whose essential normative role in providing reasons is
harmonious with the causal role of P in generating verbal and other
responses.
This will be easiest to explain with some examples (which closely
mirror some of Pautz’s own examples). Some are examples of hedonic
harmony; others are examples of epistemic harmony. We’ll also
discuss a third, somewhat overlapping type of normative harmony,
cognitive harmony, but will rely on it less because it requires a
controversial background assumption.
Here’s a hedonic example. A damaging stimulus causes physical state X,
a certain biochemical or computational state of your brain. X causes
you to avoid or eliminate the stimulus in the future. Conveniently,
the psychophysical laws map X onto the experience of pain, an
intrinsically bad experience which essentially provides one with
reason to avoid or eliminate it. So the psychophysical laws correlate
X with a phenomenal state whose essential normative role harmonizes
with the functional role of X. And this isn’t a random fluke, but a
pretty general truth about relevantly similar functional states and
their associated hedonic states: we systematically avoid unpleasant
experiences and pursue pleasant experiences. This is hedonic
harmony. To be clear, the surprising fact here is not that there is a
physical state that plays the pain role (tracking bodily damage,
producing avoidance behavior, and so forth). Presumably this fact has
a straightforward evolutionary explanation. What’s surprising is that
the actual psychophysical laws map it onto an experience whose
essential normative role harmonizes with this functional role. Since
evolutionary forces cannot affect the psychophysical laws, it’s hard
to see how an evolutionary explanation of this harmonious
correspondence would even get off the ground. (Note that we are not
rejecting the standard evolutionary explanation for why we feel pain
in response to harmful stimuli. Given that pain is lawfully linked
to avoidance behavior and the like, it makes perfect evolutionary
sense that we would experience pain in response to harmful stimuli.
But this evolutionary explanation presupposes normative harmony; it
does not explain it. There is nothing inappropriate about this
presupposition when we are doing evolutionary biology; it is not the
evolutionary biologist’s job to explain the character of the
psychophysical laws.)
Hedonic harmony seems very lucky. The psychophysical laws could
conceivably have mapped X onto pleasure, while mapping the actual
neural basis of pleasure onto pain. In this pleasure/pain inversion
scenario, we would systematically avoid a state we have reason to
pursue (pleasure), and systematically pursue a state we have reason to
avoid (pain). Our lives would be a pathetic farce: we would cower from
pleasurable experiences and happily inflict pain on our loved ones.
Alternatively, the psychophysical laws could have correlated X with
some evaluatively neutral state, resulting in a less extreme mismatch.
Either way, our behavior and functioning would be wildly out of line
with the behavior and functioning that is justified or
rationalized by our phenomenal states.
