Abstract
The purpose of this paper is to remind
those within philosophy of mind that Darwinian Evolutionary Psychology is the
leading materialist explanation of consciousness. The idea that mental
functions in living organisms manifested as a result of biological evolution
comes directly from Charles Darwin himself and now 163 years after he
introduced that idea to the scientific community, tremendous progress has been
made into understanding the evolutionary and biological basis of conscious
experience. The modern form of this theoretical framework explains the
phenomenon of consciousness as an emergent complex systems function created
within the nervous systems of living organisms. This solution solves the hard
problem of consciousness by addressing where consciousness fits into the
non-conscious universe, why subjective experience exists for organisms, and
clarifying that standard weak emergence explains how experience arises out of
nervous system functions. With Evolutionary Psychology, science has solved the
problem of consciousness.
Evolutionary
Psychology; a Materialist Explanation of Consciousness
One of the trends over the past few
years within Philosophy of Mind is the publication of multiple ‘New Sciences of
Consciousness’ which tend to begin with the claim that science has failed to
explain consciousness so far. Some of these new sciences go so far as to claim
that science was specifically designed to exclude the study of consciousness; ‘Galileo's
Error: Foundations for a New Science of Consciousness, traces the
problem of consciousness back to the foundations of the scientific revolution,
in Galileo's decision to set consciousness outside of the domain of science. I
argue that in order to solve the problem of consciousness we need to rethink
what science is’ (Goff, 2019). But did Galileo have the power to create a
boundary of inquiry for the scientific process and all subsequent scientists?
Has the last 200 years of the scientific process really excluded consciousness?
The answer to both those questions is no. There is an existing science of
consciousness; Evolutionary Psychology. University courses are even available
on the subject and significant progress has been made in understanding the
evolutionary and biological origins of consciousness. Any new hypothesis about
consciousness must compete against the existing scientific explanations rather
than be presented as filling a void left by traditional scientific methods. Within
evolutionary psychology, consciousness is explained as an emergent complex
systems phenomenon created through biological energy expenditures within nervous
systems.
One of the great insights Darwin
provided was that no species originated as they currently exist, but were all
shaped by a long process of adaptation called evolution. Decent with
modification paired with evolutionary deep time created a slow,
intergenerational development of all physical & mental traits which is
responsible for the variation throughout the animal kingdom we see today. That
insight enabled scientists to create an evolutionary explanation for mental
phenomenon like consciousness in living organisms shaped by evolution;
consciousness did not always exist, consciousness slowly developed throughout millions
of generations of living organisms. Sense organs (eyes & ears) relaying
somatic information to a centralized information processing center (the brain)
in which all sensory information was unified into a single subjective mental
experience for an organism and used to flexibly interact with its environment provided
a survival advantage so the ability was passed on. And now human mental
experience is the product of half a billion years of the evolution of
consciousness so it cannot be understood outside of its place on the
phylogenetic tree of life. All the way back in 1859 Darwin predicted that, “In
the distant future…Psychology will be based on a new foundation, that of the
necessary acquirement of each mental power and capacity by gradation. Light
will be thrown on the origin of man and his history.” Since the 1860s,
Darwinian Evolutionary Psychology has been the leading theoretical framework to
explain consciousness and we now live in that distant future Darwin envisioned.
In a 2012 Big Think lecture titled ‘The Psychology of Everything’, Paul Bloom, Professor
of Psychology from Yale University, described the field of psychology in a way
that resembles what Darwin predicted;
“Now, psychology is such a huge field that it breaks
up into different subfields. Some psychologists study neuroscience, which is
the study of how the brain gives rise to mental life. Others, like me, are
Developmental Psychologists. We study what happens to make a baby turn into a
child and a child turn into adults. We ask questions like, how does a baby
think about the world? What do we start off knowing? What do we have to learn?
Other psychologists are Social Psychologists. They study human interaction.
What’s the nature of prejudice? How do we persuade one another? Some
Psychologists are Cognitive Psychologists. What that means is they study the
mind as a computational device looking particularly at capacities like
language, perception, memory, and decision-making. Some Psychologists are
Evolutionary Psychologists, which means they’re particularly interested in
biological origins of the human mind. Evolutionary Psychologists are particularly
interested in the evolutionary origin of our psychology, so they study the mind
with an eye towards how it has evolved. What adaptive problems it’s been
constructed to solve. Finally, there’s clinical psychology. For many people,
this is what psychology means. Many people associate psychology with clinical
psychology, and in fact, it’s a very important aspect of psychology. Clinical
psychologists are interested in the diagnosis, the causes and the treatment of
mental disorders, disorders like schizophrenia, depression and anxiety
disorders. It would be impossible for me to provide a full spectrum
introduction to all of these sub fields of psychology in the time I have.”
(Bloom, P. 2012)
So rather than failure from scientific
methods to explain consciousness, science has the entire field of psychology
dedicated to studying the mind. In 2009 to commemorate the 150th
anniversary of the publication of On the
Origin of Species, the American Psychological Association published a
series of essays from leading philosophers and scientists regarding the impact
Darwin had on the field. In one of those essays, David Buss Professor of
Psychology at the University of Texas at Austin said, “Evolutionary psychology
is not a distinct branch of psychology, but rather a theoretical lens that is
currently informing all branches of psychology… Evolutionary psychology
provides a metatheory for psychological science that unites these fields.” There
is widespread scientific agreement on fundamental aspects of this metatheory
that has enabled it to be a stable theoretical lens for the whole of
psychology; that humankind is a product of evolution, that mental functions
evolved, and that the psychology of an organism is dependent on its physiology.
This theoretical lens informs the hypothesis that there is a biological basis
of mental experience; so when modern neuroscience was able to study the
correlation of brain states with conscious states, that was empirical
verification of the biological basis of consciousness as predicted by
evolutionary psychology. Evolutionary psychology places consciousness into the
physical universe as a biological function while explaining the long evolution
of nervous systems and the survival advantage mental experience serves for an
organism.
We may eventually need a new theory of
consciousness to replace Darwinian Evolutionary Psychology, but that new theory
would need to have superior explanatory power to the current leading science of
consciousness that is presently informing all branches of psychology. But how
does this theoretical lens explain how consciousness exists anyway? Well, Evolutionary
Psychology is an extensive field with much ongoing debate at the forefront of
our scientific knowledge; one of the best introductions to the field is a 5
part article series published in Psychology Today called ‘What Actually Is Consciousness, and How Did It Evolve?’ written by
Ralph Lewis which describes the similarities and differences among 5 prominent
explanations written by Daniel Dennett, Joseph LeDoux, Antonio Damasio, Michael
Graziano and one coauthored by John Mallatt & Todd Feinberg. My preferred
explanation is written by Todd Feinberg & John Mallatt and is also
described in their 2 papers ‘The
Evolutionary and Genetic Origins of Consciousness in the Cambrian Period over
500 million years ago’ and
‘Phenomenal Consciousness and Emergence: Eliminating the Explanatory Gap’.
In the first paper they present a ‘hypothesis that dates the origin of
consciousness, explains its neural architecture, explores its genetics,
identifies the most basal animal that has it, and accommodates its neurobiology
with the “hard problem” of consciousness.., all…in one model’ while the second
paper clarifies what weak emergence is and how an emergent explanation of
consciousness “adheres to and is consistent with the principles of emergence in
the rest of nature… We show how this formulation explains consciousness as an
instance of standard, weak emergence without a need for strong emergence or a
scientifically unbridgeable explanatory gap.” Or, to say the materialist
explanation of consciousness succinctly, a living organism expends energy to
power their nervous system and the nervous system is a complex system so
subjective experience emerges through biological energy expenditures + complex
system functions within an organism. So to study consciousness as a
physicalist, we need to study the complex system that produces it; “Your brain
is a hotbed of electrochemical activity. About 100 billion neurons are each
firing off 5-50 messages (action potentials) per second.…The process of sending
these signals takes place in two steps: along the cell (action potential) and
between cells (neurotransmitters)” (Khan Academy). Which allows emergence to be
a full reductionist explanation of consciousness with the reduction relying on levels
of organization studied in anatomy & physiology; the chemical, cellular,
tissue, organ, organ system, & organism levels through which consciousness
emerges.
With the best modern examples of
Darwin’s theory, science possesses a comprehensive explanation of where
consciousness comes from (evolution), why it exists at all (survival
advantage), and how it comes into existence within an organism (emergence);
which is why it is shocking and disappointing to often see the claim repeated
that science has been unable to explain consciousness. When the claim is made
that science has failed to explain consciousness, the scientific establishment
should proclaim “what we know from science is that the mind comes from the
brain and nothing but the brain. The mind is what the brain does.” (Lewis, R. 2020).
Today we live in what has been called The Golden Age of Neuroscience which is
the most exciting time in the history of the study of consciousness; it is time
for Darwinian Evolutionary Psychology to be revitalized by the scientific
community as a general theoretical framework to understand consciousness.
References
Buss,
David. “Evolutionary Theory and Psychology.” American Psychological
Association, APA, May 2009,
https://www.apa.org/science/about/psa/2009/05/sci-brief.
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Feinberg,
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in the Cambrian Period over 500 Million Years Ago.” Frontiers in Psychology,
vol. 4, 4 Oct. 2013, https://doi.org/10.3389/fpsyg.2013.00667.
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Todd, and Jon Mallatt. “Phenomenal Consciousness and Emergence: Eliminating the
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