Intent and Biology

I wanted to say a word or two about the concept of intent as it applies to biology.  This word, along with agency, will, and consciousness appears frequently within the literature on how we explain human behavior.  Within law, for example, questions of intent inform culpability.  Deliberation, premeditation, and malice are considered important aspects that distinguish murder from the less serious crime of manslaughter.  The question arises to what extent we can view “intent” and related categories as scientific concepts.

:et us look at where the ideas arise.  There is no question that intent is related to the process of decision making, so I want to start with a basic sketch of that chain of causes. We can start with external stimuli (ES).  These are forces arising outside the individual that will contribute to the decision making process.  If I’m deciding what to have for lunch, then the cry of the hotdog vendor or a suggestion by a friend might be an important stimulus.  If I’m trying to decide to leave my chair on the deck, the decreased temperature as night falls might be an important stimulus.  Along with external stimuli, there will also be internal stimuli (IS).  Am I hungry?  Am I on a diet?  Did I make an early commitment to go in the house and start making dinner?  All of these form internal stimuli.  Both internal and external forces go into the process and, since the two are mutually exclusive and all inclusive, the sum of them will be the complete set of forces influencing any decision I make.

Next there will be a decision point (DP).  I choose to get a hot dog.  I choose to go inside.

And finally, we have consequences (C) – the outcomes of my choice, both intentional and unintentional.  In the case of lunch, the hot dog might fill me up, but give me a stomach ache later.  Alternatively, crossing the street for a salad could get me run over by a passing truck.  In the case of the porch, I might choose to go inside and end up missing an amazing sunset, but will certainly be warmer.

(1)  ES + IS –> DP –> C

Within this framework, we can ask where intention (I) occurs.  Traditionally, in the West, we think of intention being a conscious act of the will before the decision is made.  It has something to do with desiring an outcome and that desire is made manifest in a concrete decision.

(2a) ES + IS –> I –> DP –> C

Alternatively, modern cognitive neuroscience suggests that our conscious justification of a decision only occurs after the decision has been made unconsciously.  Consider Benjamin Libet’s experiments, which show just this.

(2b) ES + IS –> DP –> I + C

It is entirely possible that our conscious intentions have no affect on our decisions. Alternatively, if we use intention in a way that doesn’t require consciousness, it could simply mean the set of internal stimuli immediately leading up to the decision point.

(2c) ES + IS –> I/DP –> C

Regardless of which of the three positions you take (2a-c) the question of internal stimuli still requires some thought.  In the reading group today, we discussed the possibility that internal stimuli, at the end of the day, are entirely explainable in terms of external stimuli.  And we must introduce two more terms just to avoid confusion: Internal Stimuli caused by external stimuli (cIS) and Internal Stimuli uncaused by external stimuli (*IS)

(3) ES –> cIS –> DP –> C, *IS == 0

This, I think, is one of the key questions in philosophical determinism and, more to the point, one of the key claims of evolutionary accounts of function, purpose, and teleology.  Ernst Mayr, Jacques Monod, Daniel Dennett, and others wish to claim that all local functions are really product of external forces and that those external forces are primarily (if not exclusively) natural selection and physical environment.  For them, internal stimuli represent ordered states, “programs” if you will, that tell an organism what to do in response to specific promptings.  If hungry and food is available, eat.  If cold and warmth is available, move to warmth.

Consciousness as an experience of the event is not nearly so important as the question of whether external stimuli are sufficient to fully explain the decision consequences. Evolution by natural selection provides an immensely useful way of looking at how external stimuli (natural selection in a consistent environment) might cause such internal programs to come into being.  At this point there seems to be no question that the internal stimulus “desire to eat fatty foods” has come about (at least in part, quite possibly in its entirety) from a time when fatty foods were scarce and individuals who ate them whenever available were more successful than other members of the same group.

Some IS must come from ES. The only question is whether all IS come from ES.

I believe science is in an awkward position here.  For me, science can only deal in “mutual observables,” phenomena that can be repeatably noted by multiple observers in the same way.  I see no way for internal states to be observed.  Hence, from the standpoint of science.

ES + *IS –> C should look exactly the same as ES –> C

I can think of no way to prove that there is no *IS on the left hand side.  Any good scientist will point out, however, that, if we could fully account for ES and C and we could explain all the effects in C in terms of consequences of ES, then *IS becomes negligible.  It doesn’t matter whether it sits on the left if it isn’t doing any work that changes the right.  Parsimony dictates that it should be left out of the equation.

Science must favor model (3) until such a time as ES –> C is proven false.

Unfortunately, we have a strong experience of *IS in our daily lives. We think we make choices which are not fully determined by external stimuli.  Christianity in particular is committed to the idea of *IS being produced by the mind, will, soul, or spirit, which is not forced to act in a particular way by ES.  [Though note that there are historical constructions of Christianity that do not require this.  Notably “traducianism.”  It is Thomas Aquinas and “soul creationism” that fix this problem in Christianity at least by the 13th century.]

Some philosophers, wishing a scientific explanation for IS, have started using *IS language (agent, will, intent) within cIS models.  This may be necessary, as all of the IS language is *IS language historically.  Alas, it really stifles communication, because insisting on cIS meanings for all the IS words makes the traditional *IS literature unreadable (Aristotle really means *IS motion, Aquinas really means *IS will) and deprives the common conversation of any words to talk about the issue at hand.

We need a vocabulary (less clunky than *IS and cIS) to talk about the possibility of internal stimuli which are (or are not) fully caused by external stimuli.


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