Monday, April 19, 2010

Argument against the 'Brain Death' Criterion for Death


P1) If a ‘brain dead’ patient shows signs of vital activity, then that vital activity must be caused by a soul.
P2) If vital activity is being caused by the soul, then the soul must be present, informing the body.
P3) If the soul is present, informing the body, then there is a soul-body composite.
P4) If there is a soul-body composite, then the patient is alive.
P5) ‘Brain dead’ patients show signs of vital activity.
C) Therefore, those patients are alive.


Gregory the Eremite said...

I agree; but I think one might need to address the following in order to be convincing:

Objection: In a brain dead patient, it seems that the rational soul has been replaced by a sensitive soul.

Don Paco said...

Good objection. Here's my reply followed by a defense.


P1) If the rational soul has been replaced by a sensitive soul, then the human body must be replaced by the body of a brute animal.

P2) But in the case of the brain-dead, the body remains human.

C) Therefore, the rational soul has not been replaced by a sensitive soul.


Proof of P1: The ultimate reason for this premise is that the soul is the act of the body. The body's actuality, characteristics, and end are reduced to the soul as to their formal cause. So a sensitive soul would inform matter in such a way as to cause a body with a non-human end, and thus with suitable organs ordered toward this end.*

Proof of P2: All the (remaining) organs in the body of someone who is 'brain dead' are ordered to rational activity.**

And the conclusion follows.


*Cf. Aquinas' Commentary on Aristotle's De Anima, Book I, Lecture 8 (Chapter 3):

[Refutation of Pre-Socratic and Platonic Psychology] "§ 130. The tenth argument starts at ‘Another absurdity’. It is effective not only against Plato, but against many others also. It runs thus. It is clear that there must always be some proportion between mover and moved, agent and patient, form and matter. Not every form suits every body in the same way, nor does every agent act upon every patient. Nor, again, does every principle of movement move everything capable of receiving movement. There must be some correlation and proportion between them by which the one is naturally the mover, the other the moved in each case. Now obviously these philosophers admitted that the soul was in the body and moved it. Since then they spoke of the nature of the soul, it seems that they should also have had something to say about the nature of the body; about why the soul is joined to the body and how the body is related to and contrasts with the soul. Their study of the soul was inadequate so long as they discussed it alone and neglected to explain the nature of the body that receives it.

§ 131. Indeed, we may associate their thesis (Aristotle goes on to say) with the Pythagorean fable that any soul can enter any body; the soul of a fly for instance might perchance enter the body of an elephant. This cannot in fact happen; for the body of each particular thing, and especially of living things, has its own form and species and type of movement: hence there are great differences between the bodies of a worm, a dog, an elephant and a gnat. When they say that any soul can enter any body, it is as if one were to say that the art of weaving could enter flutes, or that the art of the coppersmith could enter a weaver’s loom. If it was in the power of these arts to enter bodies or instruments they would not do so indiscriminately, but the art of playing the flute would enter flutes, and not lyres, while the art of playing stringed instruments would enter stringed instruments and not flutes. In the same way, if there is a body for every soul, any soul does not enter any body; rather the soul shapes the body fit for itself; it does not enter a ready-made body. Plato and the others who speak only about the soul are too superficial; they fail to define which body answers to which soul, and the precise mode of existence of each in union with the other."

**Cf. also the Aristotelian principle that human bodily organs are the way they are on account of the form of man (i.e., the rational soul):

Don Paco said...

Another reply:


P1) If the rational soul of a female patient who is 'brain dead' has been replaced by a sensitive soul, then the resulting animal would not be able to generate a human being.

P2) Female patients who are 'brain dead' can conceive and bear healthy human children.

C) Therefore, the rational soul of a female patient who is 'brain dead' has NOT been replaced by a sensitive soul.


Proof of P1: Omne agens agit simile sibi, "every agent causes something similar to itself." Only a human being can generate another human being.

Proof of P2: This is evident from several cases.

Jamie said...

In your first defense of the objection I am curious about point two - isn't this begging the question?

Gregory the Eremite said...

Bravo! Both proofs are, of course, correct, but the second is a thing of beauty.

Don Paco said...


YOU SAY that I beg the question when I say the following:

"Premise 2) But in the case of the brain-dead, the body remains human....

Proof of Premise 2: All the (remaining) organs in the body of someone who is 'brain dead' are ordered to rational activity.

I imagine that you mean this: the defense of the premise, in saying that:

"the organs in the body are ordered to rational activity"

already assumes the conclusion of the argument, namely, that:

"the rational soul has not been replaced by a sensitive soul."

IN REPLY, I would say that, our knowledge of the proposition:

"The organs in the body are ordered to rational activity"

is prior to (and independent of) our knowledge of the proposition:

"the rational soul has not been replaced by a sensitive soul."

The basic principle on the basis of which I say this is the following:

Whereas in the order of reality, causes are (metaphysically) prior to their effects, in the order of knowledge, effects are (epistemologically) prior to their causes: i.e., we know effects first, and that's how we obtain knowledge of their causes.

So in the order of reality, the soul is the cause of such and such an organ being ordered to such and such end (e.g., the rational soul is the cause of human hands being ordered to a rational end); but in the order of knowledge, we first must know the end to which the organ is ordered, and that allows us to know what kind of soul is causing that teleological order.

In the case of the organs of the 'brain dead' patient, it is clear that all of those living organs are designed in such a way that they would be most fitting as organs of a rational being, and would NOT be fitting for an irrational animal; e.g., hands are 'the tool of tools', because, better than any other animal organ, they allow a rational being to manipulate his environment in a rational way:

"It is the opinion of Anaxagoras that the possession of these hands is the cause of man being of all animals the most intelligent. But it is more rational to suppose that his endowment with hands is the consequence rather than the cause of his superior intelligence. For the hands are instruments or organs, and the invariable plan of nature in distributing the organs is to give each to such animal as can make use of it; nature acting in this matter as any prudent man would do. For it is a better plan to take a person who is already a flute-player and give him a flute, than to take one who possesses a flute and teach him the art of flute-playing. For nature adds that which is less to that which is greater and more important, and not that which is more valuable and greater to that which is less. Seeing then that such is the better course, and seeing also that of what is possible nature invariably brings about the best, we must conclude that man does not owe his superior intelligence to his hands, but his hands to his superior intelligence. For the most intelligent of animals is the one who would put the most organs to use; and the hand is not to be looked on as one organ but as many; for it is, as it were, an instrument for further instruments. This instrument, therefore,-the hand-of all instruments the most variously serviceable, has been given by nature to man, the animal of all animals the most capable of acquiring the most varied handicrafts." (Aristotle, Parts of Animals, VI.10).

Click here for a nice account of why Aristotle thinks that human hands can only be the hands of a rational being.

Anonymous said...

Objection to the second reply:

I distinguish the major; (1) that only a female with a rational soul can produce the material cause of generation (ova), I concede; (2) (a) that the woman must still exist when the act of generation occurs and (b) that only a member of the same kind can nurture another before birth, I deny.


(2a) This is evident especially from certain cases of in vitro fertilisation.

(2b) This also is evident from the development of fetal mules in horses.

Francisco Romero Carrasquillo said...

Anonymous, your objection leaves me wondering what you understand by 'generation'. Are you saying that ovulation is truly the act of generation, and that conception is not?

Moreover, do you concede that 'omne agens agit sibi simile'? If so, how does this occur in human conception? If it is a corpse that conceives, how could we say that the zygote is 'simile' to the corpse?

I would reconsider what generation is. Ovulation is not generation. In fact, ova are produced before ovulation. Ovulation merely releases the pre-existing ovum. All of this is merely preparatory for generation. The real act of generation is fertilization and conception. A 'brain-dead' female patient cannot ovulate once she enters that state, but she could ovulate before that state, and conceive AFTER. The act of generation takes place after that state. And since omne agens agit sibi simile, it follows that the agens that agit a human conceptum must be human. Ergo.