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The Cockroach's Soul

Sir Edward Burne-Jones. The Mirror of Venus.
Reflexion and free will are impossible without a spiritual soul.
(Sir Edward Burne-Jones. The Mirror of Venus. Source)

Table of contents

1) Introduction
2) What is a "soul"?
3) What are the different types of souls?
4) What is the nature of vegetative and sensitive souls?
5) Can computers have artificial intelligence?
6) Are monkeys intelligent?
7) Isn't it unscientific to talk about spiritual souls?
8) How could a soul so obviously conditioned by matter be spiritual?
9) When does the spiritual soul begin to exist?
10) Conclusion

1) Introduction

Do cockroaches have a soul?

Why would any sane person worry about such a question? In a nutshell, because the answer to that question determines whether or not there is a difference between putting a log in the woodstove, and putting a Jew in a crematory oven. In other words, at some point of time we have to ask ourselves whether men are strictly material beings like rocks, logs, rabbits, cockroaches, etc., or whether they are very different.

We all know that men are animals, that they are at least material beings. But are they also more than just material beings? Do men have souls? Do men have something that gives them some kind of special dignity?

I'm far from an expert, but I'll try to give you an outline of the solution, and then beg you to consult real philosophers (like Aristotle, Saint Thomas Aquinas, Thonnard, or eventually the OSThoPhiT).

2) What is a "soul"?

Here is an easy mathematical question: How old is the captain? "Which captain?", you say? It doesn't matter. How old is he? Come on! You know the answer! The captain is X years old! There, you know the answer! You can then build equations, so if somebody tells you that if you double the captain's age, then he is as old as one tenth of the age of your home town in Europe which is 890 years old:

	2 * X = 890 / 10
	X = 44.5 years old

By starting with this X, this unknown, you can "fill in" your knowledge of X progressively.

The word "soul", when used by Aristotle and Saint Thomas Aquinas, is a bit like "X" for mathematicians. It's a technical term. There is a difference between a non-living being (like a rock, or a penny, or a bicycle), and a living being (like a dandelion, a dog, or yourself). What makes that difference? What does the dog have, that the rock doesn't have? A mathematician would say "X is what makes the difference". Philosophers preferred to use the word "soul" ("anima" in Latin, "psyche" in Greek).

This means, surprisingly to some people, that cockroaches have souls, technically speaking.

3) What are the different types of souls?

There are obviously differences between dandelions, dogs, and us. Since the soul is what makes living beings be alive, then their different "ways of being alive" will be determined by their different types of souls:

3.1) Vegetative soul. Such beings can feed themselves, grow and reproduce. This includes dandelions, trees, bacteria, etc.

3.2) Sensitive soul. Such beings, on top of being able to do everything vegetative beings do, are also able to (normally) move themselves and perceive their environment with their senses (sometimes only the sense of touch). This includes dogs, snails, birds, etc.

3.3) Intellective soul. Once again, these beings can do everything the others can (vegetative and sensitive), with the addition of reason and free-will. This includes only men, whether male or female.

4) What is the nature of vegetative and sensitive souls?

The general principle is technically known as "Agere sequitur esse", which could be translated as "the actions flow from the essence". A hockey stick doesn't bark and run around, because it doesn't have the nature of a dog, but the nature of a hockey stick. So knowing the typical operations of beings with vegetative or sensitive souls, what is the nature of their souls?

Aristotle, over two thousand years ago, observed that beings with vegetative or sensitive souls don't have any operations which cannot be explained by matter alone. In other words, the soul of a cockroach is purely material. Aristotle went as far as saying those souls were in the category of "geometric figures".

This fits perfectly with what we know today about most living organisms. If you go to the local hardware store and buy several cans of atoms (Carbon, Hydrogen, Oxygen, Nitrogen, Sodium, etc.), and if with really, really small tweezers you manage to assemble these atoms in just the right way, you'll get a living organism. OK, practically speaking it's not as easy as that, but conceptually it would work.

Another way of looking at this would be to think about a barbecue pit. If you take a heap of bricks, you have only a heap of bricks! But if you assemble those bricks with the proper geometric figure, you have a barbecue pit! You could say that the difference between a heap of bricks and a barbecue pit is "X", or a "soul". Notice that if you "removed the soul" from your barbecue pit (by kicking it, for example), you'd have a heap of bricks, but you wouldn't see a "barbecue pit soul" float away like some kind of ghost!

Remember, this is not only according to Catholic philosophers like Saint Thomas Aquinas (thirteenth century), but also Aristotle, over two thousand years ago!

Now what about the human soul? Is it also purely material?

It seems to me that the logical approach to this problem is to first ask ourselves: "Could the intellective soul be material?" If we can find things that can do everything men can do, but who don't have spiritual souls, that would be a strong argument against the spirituality of the human soul. So let's look at the two best candidates: computers and monkeys.

5) Can computers have artificial intelligence?

Could a super-advanced computer become like a human person? Is it possible to build a computer that would be intelligent? As usual, the answer depends on how we define terms like "artificial intelligence".

The expression "artificial intelligence" was apparently invented in 1956 by John McCarthy [Russell and Norvig. Artificial Intelligence; A Modern Approach, 2nd Ed., p. 17]. I don't know if at that time a debate occured comparing the two candidate expressions: "artificial intelligence" and "artificial instinct". We do know that cats and dogs can behave quite cleverly, that monkeys have emotions (like anger or fear), and that even lowly insects can do wonderfully complex things, like weave a spider web. We've known for thousands of years that instinct is a marvel of Nature, and that instinct is purely material (see #4 above), hence instinct is something we can build artificially.

So why doesn't anybody use the expression "artificial instinct"? I would say it's a case of verbal inflation. (You can probably get bigger research grants from the U.S. Military if you claim you can invent "artificial intelligence"!) But regardless of the terminological debate, many remarkable computer programs prove that "artificial instinct" exists as we speak today, and will only improve.

Simple sensor-controller-actuator loop.
Simple sensor-controller-actuator loop.

How far can "artificial instinct" go? The most complicated computer imaginable can theoretically be built using only faucets and garden hoses (see among others The Water-Computer). You also need actuators to act on the surroundings (like hydraulic jacks, or electric motors, etc.), and sensors to detect changes in those surroundings (usually various devices that transform some physical phenomena into variations in an electric signal, like photoreceptors, or pressure transducers, etc.). Given enough time, you could then build a very sophisticated robot that looks like a man. You could then program your robot to behave intelligently:

   while not sleepy
      look around with eyes
      if detect a donut
         eat donut
      else if detect face
         perform face recognition
         if face = wife
            say "Hi Marge, I love you!"
         else if movements of face = commands sent to my actuators
         	check in mirror for pieces of donut stuck in my teeth
            say "Hey you! What are you doing in my house?"
         twiddle thumbs

How intelligently could your robot behave? Could you build a "fireman robot" that would be clever enough to rescue people trapped inside burning houses? Sure, why not? Could you build a "surgeon robot" that could operate on a patient to remove his infected appendix? Sure, why not? If you can invent sensors that are sensitive enough, and actuators that are powerful and precise enough, and if you can connect those sensors and actuators to a fast computer in which you've loaded a very clever program, in theory in can be done.

But there is a difference between behaving intelligently and being intelligent. "Artificial intelligence", strictly speaking, would require pure matter to have self-awareness and free-will. How do you connect garden hoses and faucets in order to produce self-awareness? Material changes are "transitive", i.e. one object acts on another object, like a domino that strikes another domino. But in self-awareness, the change is "immanent" not transitive. In other words, what is self-aware is simultaneously object and subject, "seen" and "see-er". How can a material thing be in two places at the same time?

Moreover, how do you connect garden hoses and faucets to have free-will? Any computer program can select one of many options, but it doesn't freely choose. It just follows the program! A programmer can easily incorporate a "randomizing" element in the decision function (the equivalent of flipping a coin). The programmer can therefore make the robot's behavior as difficult to predict as he wants. But the computer still doesn't have free-will! The computer would need to be self-aware, to be "transparent to itself". Then its "conscious self" could decide, while setting aside its program and any randomizing functions. But how do you connect garden hoses and faucets in order to produce self-awareness? Oops!

6) Are monkeys intelligent?

Many people these days claim monkeys (or gorillas, or dolphins, etc.) are "intelligent". One popular claim is usually like: "Koko the gorilla can speak using sign language, therefore she can think!" Except the "Scientists" who make such claims are usually long on the description of the "wonderful language skills" of their subjects, and short on reality checks.

First, why are such supposedly "intelligent" beings insulated from us by specialized animal trainers and strange languages? Is your gorilla really intelligent or not? If it is, then you don't need to teach it some fancy sign language! That gorilla has perfectly good ears, so just ask some "yes or no" questions, and it will nod to answer. In the movie Ratatouille (see picture here below), the cook finds out in a few seconds that the rat in front of him is an intelligent person, just by asking a few questions. No need for an interpreter, and no need to spend years teaching it sign language!

  Did you just nod?
"Did you just nod?"
Source: Ratatouille, © Disney/Pixar

What? Koko the gorilla has not learned to understand what we say? How come every baby in the world learns to understand speech just by listening, but not your gorilla?

Second, just count the number of monkeys (or dolphins, or gorillas, etc.) who are reading this article!

Third, we must not forget the marvels of animal instinct. A beast devoid of reason can behave cleverly, if you train it long enough. Even pigeons (who have bird brains!) can do amazing things, if you have enough patience and bird seed!

How can we tell the difference between training, and intelligence? I suggest a practical experiment: Attach an electric wire to Koko's trainer, and connect it to a power supply able to give painful shocks. Connect the wire to some sort of complex mechanism in another room where Koko is. Get a person who can use sign language, but whom Koko has never seen, and who doesn't have any bananas to give to Koko. Ask this person to explain to Koko how to defuse the shock-giving mechanism. I bet that Koko will convince his trainer that animals can't talk, never mind think!

Seriously, although that practical experiment works, it's not theoretically sound. Even I could build a robot that could pass that "Electro-Koko Test", and it would have a "brain" made of garden hoses and faucets! If all an "intelligence test" does is to detect molecules moving around, that test cannot prove the presence of an intelligence. Matter is matter, and matter moving around mostly proves that there is matter moving around! The ultimate test would be to directly observe self-awareness and free-will, the way we directly observe, for example, red blood cells in a microscope. Except we can only directly observe our own self-awareness and free-will! So all we can do is "bang on the walls of materiality", in an orderly way, and listen for some orderly bangs in return. Since we can reflect on the nature of order, and see order needs to be caused by an intelligence, we can detect intelligence by listening for "orderly bangs in return". With enough bangs, we can eventually conclude whether the source of those "orderly bangs in return" is something that was designed to behave in an orderly way (like a computer or a beast), or another person (i.e. something endowed with self-awareness and free-will).

7) Isn't it unscientific to talk about spiritual souls?

Computers and monkeys do not have self-awareness and free-will, but men do. Many philosophers claim that a spiritual soul is necessary to have self-awareness and free-will. Is this true? Let's first look at some common misconceptions about the teachings of Aristotle (and the Catholic Church) concerning the spirituality of the human soul:

7.1) "Scientists have never detected spiritual souls with their instruments". Absolutely true! By definition, if something is spiritual, it doesn't have mass, temperature, size, etc. If there is such a thing as a spiritual world, then our only "entrance" into that world is necessarily the careful analysis of certain operations of our soul (thought and free-will). The only "spirituality-detector" there can be is our own conscience.

7.2) "The only way to claim our soul is spiritual is to use Religion, not Science". False! Aristotle didn't say: "Jesus Christ said we had spiritual souls, therefore that is Scientific truth!" First of all, Aristotle lived long before Christ, and secondly Aristotle, being a good scientist, tried to assert only when the facts twisted his arm. The nature of the human soul is know by its operations. If some of these operations cannot be performed by a strictly material soul, then we will have to admit that the human soul is spiritual.

7.3) "Spiritual souls are for crazy people who believe in reincarnation and ghosts". Partially true, and partially false. Yes, there are plenty of crazy people who believe in ghosts and reincarnation. But good philosophers, like Aristotle and Saint Thomas Aquinas, explain why reincarnation and ghosts are impossible, by the very nature of the union between the body and the soul of man. Technically, it's called "Hylemorphism", and it's a solid, well-balanced explanation of the very intimate union of primary matter and substantial form. The full explanation requires the study of Metaphysics.

8) How could a soul so obviously conditioned by matter be spiritual?

If we suppose for a moment that the human soul is spiritual, we immediately run into a whole series of arguments that revolve around the obvious material conditioning our our thoughts and behaviors. Entire medical textbooks have been written, describing how our material body influences, and even sometimes apparently destroys our reason and free-will. Does this prove that it's impossible for the human soul to be spiritual?

No. But it does prove that there are many philosophers who are wrong, even though they claim we have a spiritual soul. Several inferior philosophers (like Plato and Descartes) claim that the human soul is spiritual, but only accidentally united with the body. Such philosophers often claim spiritual souls are "punished" by being thrown into material bodies, and that being connected to a material body is a hindrance to thought.

But Aristotle and Saint Thomas Aquinas (and the Catholic Church) never said that. On the contrary, they say things like:

8.1) Nihil est in intellectu quin prius fuerit in sensu. All the positive and direct content of our thoughts is taken from sense experience [Thonnard, PDH, 548].

8.2) Non datur intellectio sine conversione ad phantasmata. There can be no act of intelligence without returning to some sense datum [Thonnard, PDH, 548].

8.3) A man thinks with all of himself, body and soul. "Yet to say that it is the soul which is angry is as inexact as it would be to say that it is the soul that weaves webs or builds houses. It is doubtless better to avoid saying that the soul pities or learns or thinks and rather to say that it is the man who does this with his soul." [Aristotle, De Anima, book 1, chap. 4].

Aristotle and Saint Thomas Aquinas claim that the human intelligence is the weakest of all intelligences (below angelic and divine intelligences). Our thoughts are clearer and stronger because of our bodies, a bit like our flesh is made stronger by being supported by our skeleton (notice how even here in this very sentence, I'm using matter to help us think about very abstract thoughts!).

That being said, our mind's dependency on our body is objective and extrinsic. "Objective dependency" because our intelligence must think its direct object in sense experience, but "extrinsic dependency" because the actual characteristics of our thoughts show our intelligence is fully independent of material conditions. The complete scientific proof is given here by Thonnard, but any other good Philosophy Textbook will do.

Now the flashlight exists, and now it doesn't?
Now the flashlight exists, and now it doesn't?

9) When does the spiritual soul begin to exist?

Look at the image here above. A flashlight can be turned on, and it can be turned off. There is something that can project light, and this thing continues to exist, even when no light is actually projected. In technical terms, a turned off flashlight is "in first act", and when it's turned on, it's "in second act".

This has many similarities with the human soul. Yes, we can make acts of self-conscience and will, but we can also be sleeping, or be under general anesthesia during a surgical operation, etc. The source of second acts doesn't cease to exist when it's in first act.

In that case, when does the human soul begin to exist "in first act"? In other words, what is the moment of "ensoulment" of the spiritual soul in a body? Of course, the problem is that we can't see, nor touch, nor taste a spiritual soul. We can prove a human adult has a spiritual soul. Then we can prove, by coming back more and more in time, that it's the same living being which lasts through time. But up to when can we go back in time, and still have before us a man, i.e. a being endowed with a spiritual soul and a body?

Since a spiritual soul doesn't take up any room, we can't base ourselves on the size of the living being in front of us. And since a spiritual soul can be in first act only, we can't base ourselves on the temporary absence of actes of reason and will. (Especially if the living being in question is building all the instruments it needs for a spiritual soul to go into second act!) Moreover, you'd have to be really clever to find a break or clear discontinuity in the development of that living being, after conception. (And I repeat in other words: especially if the living being in question is adding all this complexity, without this complexity coming from outside itself!)

On top of all these physical difficulties, we have to add an ethical difficulty. The traditional example is that of the hunter who sees something moving in a bush. Is it a deer, or is it a man? If that hunter shoots, without knowing what he's shooting at, he acts badly. As long as he's not certain there is no man in that bush, he must avoid shooting. "Not sure? Don't shoot!"

10) Conclusion

The question of the human soul is a crucial question, on which depends most if not all of Ethics. If our soul is purely material, then there isn't a big difference between putting a log in the woodstove, and putting a Jew (or any other man) in a crematory oven.

If we do have a spiritual soul, then this immediately raises many other questions, like "What exactly is killed by an abortion?", or "Where does this spiritual soul come from?", and especially "What happens to this soul after death?"

The nature of the human soul can be known by the true Faith, i.e. Catholicism, but it can also be known by honest, humble and rational Science.

But not by cockroaches!

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