D’Holbach’s Deterministic Philosophy of Mind
I. Holbach's Metaphysics and How It Drives the Problem
Holbach starts by suggesting that:
(1) man is connected to the laws of universal nature
(2) man is entirely subject to those laws
--(3) man is not free
By "man is connected to the laws of universal nature" Holbach means that (a) there are
natural law, and that (b) man is connected to them. By "natural laws" he just means the
Hobbsean picture of "patient and agent" causation. If it is the case that when agent A
comes into contact with patient B, result C occurs, then there is a natural law stating that
A + B --- > C
So whenever A and B come into contact, C must result. It is a law.
Now by claiming that man is connected to those laws, Holbach just means that if any part
of me represents A, and I come into contact with B, then C will result. Maybe A and B
are both elements of me. Either way, I am subject to the laws of nature as they exist, and
so I am not exempt from them. A very simple way to put this:
If you place a flame under a solid object long enough, it will burn.
Let's say that this is a natural law. Well, if so, then if you place me over a flame for long
enough, I will burn too.
What about (b) -- that man is entirely subject to the laws of nature? Here Holbach is
suggesting that there is nothing about a human being that escapes the material world, and
since everything about material nature is subject to natural law, so are we.
What view would this be rejecting? Essentially, this is a rejection of dualism. "Dualism"
is an old philosophical theory (we find it in ancient Plato, in 1500s Descartes, and in 1996
articles by Jerry Shafer, a contemporary philosopher). It claims that "being" or "reality"
has two ways of manifesting itself, either as material or as mental. Material things are
"corporeal" -- chairs, atoms, books, dogs, etc. "Mental" things are "non-corporeal", and
this includes spirit, mind, God, etc. Now, if you are a dualist, then you might suggest that
natural laws obtain only for material things . So whatever has "body" (corporeality) is
subject to universal laws of cause and effect.
If you believe this, you think that all of the physical world is, in fact, subject to
determinism.
But as a dualist, you think that the mind is not physical. If the mind is not physical, then it
is not subject to the laws of cause and effect. If so, then mental "events" (like thoughts,
decisions, beliefs, ect) are not subject to determinism. Thus, a dualist can argue that since
mental events are not subject to determinism, there is no problem with respect to free will,
since freedom is a property of the mind.
This would be a fine solution (well, maybe) but Holbach denies dualism. He is a
physicalist. A physicalist believes that all that exists is corporeal. Thus, a physicalist will
explain "mental events" as corporeal events. They will argue that ideas, beliefs, decisions,
are all really just complex manifestations of brain/neuron physiology. A set of neurons
fire in the right way, and we have a certain kind of thought.
This explains Holbach's (b): he says that man is entirely subject to the natural laws. In
other words, everything that describes what a man is, is physical, and since this is the
case, everything that is man is subject to natural laws. As such, thoughts and decisions
and ideas are subject to determinism. If so, there is no free will.
II. Holbach's Basic Perception-Action System
The field of cognitive psychology views all living things as basic or complex
"perception-action" systems. Holbach is, essentially, an early cognitive psychologist in
his view on how/why man does what he does.
What Holbach is not concerned with is metaphysical causation . He does not argue "since
the Big Bang occurred the way it did, it is inevitable that you now make the decision to
drink the water from the fountain". Holbach is more concerned with larger-level
causation.
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Why is it that we make the decisions we do?
What drives us to act in certain ways?
For Holbach, what explains human behavior are psychological laws. Of course, since
man is just a physical being, all psychological laws 'reduce' to physical laws. But
Holbach is not concerned with the actual microphysical laws. Here's an example:
"If a man has the instinct to survive, is dying of thirst, sees a fountain, and believes the
fountain full of water, then the man will drink the water".
This law is "psychological" because it refers to things like beliefs and desires and
perceptions. Why does Holbach think it is true?
Let's look at a perception-action system first.
A. Basic PA System
Imagine a car which has two photovoltaic cells, one called A and the other called B. A is
stuck to the left front fender of the car, and B is stuck to the right front fender. Now
imagine that there is a wire that runs from A to the right rear tire, and a wire that runs
from B to the left rear tire. Furthermore, it is set up such that if A is activated by light, a
charge runs through the wire and activates the right rear tire, and the same with B.
The car's operation is simple. Given a light source, this basic "perception/action" system
is designed to drive and turn itself towards that light source. It is a "perception/action"
system because based on:
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(a) what the car "perceives" (how light affects the photovoltaic cells)
(b) how the "perception devices" (the PV cells) are hooked up to the machines
wheels
We can determine what the car will "do" or how it will "act". If it "perceives" light to the
left, it will "act" and turn left. The basic PA system treats perception as "input", runs it
through a basic program that tells it what to do with that input (the wiring) and thus
results in a specific "output" (the moving).
B. Man as a Basic PA System, Why Man is Not Free
How is man a perception-action system? Let's run through some basic examples to flesh
out how this could be.
Let's imagine that a man comes across a fountain of water, and perceives it (optically).
Does this in itself entail that the man will do anything? In other words, does mere
perception entail action in this case? No! The analogous case here would be if we
constructed the photovoltaic car by putting the PV cells on, but never connecting those
cells to the back wheels. If this were the case, would we have any reason to believe that
mere perception of the light leads to action? Of course not.
What we need is the "wiring".
So what does Holbach think is the "wiring" component of the human perception/action
system? Basically, he says so, claiming that what moves the human being (or as he puts it,
what moves the will) are motives.
What are motives? Motives are, Holbach thinks, desires that the human being has. Some
of these desires are "hard wired" (we have them at birth) and some are not (we acquire
them after birth). Some "hard-wired" desires might be "I desire to stay alive" or "I desire
to avoid pain". A non-hard wired desire might be "I desire a Coca-cola" or "I desire to
learn philosophy".
Now let's say that the human being in front of the fountain has some motives added to his
"system". He has the desire
"I desire to stay alive"
and in this situation the man is actually dying of thirst. So the man also has the desire
"I desire something to drink".
Okay. Now we're got three components of the human PA system. We've got (a) the object
(the water), (b) man perceiving the water, and (c) man desiring something to drink.
Is this enough to move the man to act? Not yet. What's missing? Well, simply put, the
man has to know that what is in front of him is water. If he does not know that the
fountain is full of water, he will not act on his desire and move to the water and drink. So
we need to add beliefs . The one we want is
"I believe that this body of liquid in front of me is water"
Is this enough to drive the man to act? Yes! And in this way, man is nothing more than a
more complex perception/action system. He/She sees things, has certain desires, beliefs
about those objects seen, and all of this results in determined action.
If this is determined, then man cannot be free because
(1) man does not control what he sees
(2) man does not control what he desires
(3) man does not control what he believes
If I do not control all of the components of the perception/action system, then I cannot
control what it does.