On Philosophy

April 30, 2006

Determinism and Moral Responsibility

Filed under: Ethics — Peter @ 5:03 pm

Some feel that if one truly embraces a materialist view concerning the world, meaning that there is no such thing as a mental substance, and that all is physical, then it becomes nonsensical to talk about moral responsibility, as it is really the physics of the situation and not the person who is responsible. Before I discuss why this is a false conclusion I must make clear some of the assumptions the argument I am presenting will be making. First I am making the assumption that materialism or physicalism necessarily implies determinism, at least with respect to free will. Some might object that quantum physics invalidates this assumption, but realistically quantum uncertainty does not make you freer than you were before. It seems unlikely that you have any influence over how quantum states in your brain collapse, since you do not directly observe the contents of your brain in any fashion that would cause them to collapse (how active is neuron #296 in your parietal lobe at the moment?). Even worse (for free will) if the multiple worlds interpretation of quantum mechanics is correct than you are constantly taking all possible courses of action, moral and immoral. My other assumption is that we are considering the impact of determinism with respect to a moral theory that holds that goodness is an objective fact, not an artifact of our language. There are coherent views which propose that our use of “good” is simply a linguistic device, used to influence the actions of other people, and such a view would not be affected by determinism, while a view holding that the good was an objective fact would, since such views usually hold that one can only be moral or immoral where one has a choice in one’s actions.


First let me show why it is still rational to punish people for their actions in a deterministic universe. The goal of punishment is to prevent the wrongdoer from making their particular mistake again, as well as to make an example that will dissuade others from doing wrong. Both of these goals are still obtainable under determinism. For example even if the wrongdoer’s future actions are completely determined by the current state of the world it is still reasonable to assume that their future actions would be different in a world that includes them being punished versus a world that did not include their punishment. (In a quantum mechanical view the probability distribution of their future actions would be affected.) Likewise the inhabitants of a world that includes punishment will behave differently than a world that does not. The key idea here is that determinism doesn’t imply that a person’s actions are fixed by themselves but are fixed with respect to the state of the entire universe; there is still cause and effect in a deterministic universe.

Moral Responsibility

As you would expect moral responsibility is harder to deal with than the practical issue of punishment. We wonder if it makes sense to simply blame the world for one’s actions (“physics made me do it”). However the natural laws cannot be the cause of an action, although they determine how interactions between particles proceed they do not actually interact with the particles. If an electron is bumped out of its orbit by a photon the cause is the photon, not natural law. Thus the cause of a person’s actions is the biological processes in their brain, not natural laws. Of course these biological processes themselves have causes, namely their earlier states as well as earlier input from the outside world. The primary cause for any state in the biological system in question however is usually an earlier state of that very biological system. In more conventional terms we would say the primary cause of a brain state is earlier brain states. However since we are accepting materialism as one of the premises of this argument this is the same as saying that the person is the cause of their actions. What about those earlier inputs? Well they do contribute somewhat the person’s actions, so perhaps we should say that the person is mainly to blame, although their school teachers (for example) share some of the responsibility because they did not instruct them correctly. This description of the cause of a person’s actions is the same as that which we get when we analyze them under a free will theory, which means that our notions of moral responsibility are not affected by determinism.

Who Is Conscious?

Filed under: Mind — Peter @ 1:08 am

The problem of other minds has been a classic issue in philosophy. How do we know that the people around us are conscious in the same way we are? More recently this question has also been applied to artificial intelligence as follows: how do we know if a computer is conscious in the same way we are? The solution, to both these problems, is widely considered to be the Turing Test. In such a test we engage the subject in a dialogue. If the subject answers “intelligently” we judge them to be conscious. The Turing test then seems like an easy way to divide the conscious from the non-conscious, and thus neatly resolve the problem of other minds.

The test is supposed to guarantee that the subject is conscious in the following way: First we assume that there are only two ways intelligent responses can be generated. One way is to actually be a conscious being. The other is to respond with pre-generated intelligent answers, which implies that the answers have been designed by an intelligent being and the non-conscious machine figures out which one to use by examining its input and comparing it so some kind of complicated look-up table.* However we know that the look-up table method will fail because the machine only has finite resources with which to store answers and rules. Because any question could be asked at any time by the interrogator such a machine would quickly reveal itself to be non-conscious by being unable to find an appropriate intelligent response.**

However the Turing test has a fatal flaw that makes it usable only practically and not conceptually to divide the conscious from the non-conscious. The flaw is that there are at least two ways, in principle, of creating finite machines that could fool an interrogator for the duration of any finite conversation. Method one is to have time travelers design your machine. Since they know before hand which questions will be asked it would be easy for them to pre-program a small set of intelligent answers that would fool the interrogator perfectly. If you don’t have access to a time machine you could instead create your machine by predicting the future. Obviously you couldn’t predict the future of the entire universe with finite resources, but in principle you could predict the local future with a great degree of accuracy given enough data. Even taking into account quantum mechanics, which would imply that you must account for many possible futures, you could still design a machine with a small set of answers that could fool the interrogator.

Admittedly neither of these machines is practically feasible, which means that the Turing test is still a good judge of consciousness in practical cases, but because it can fail in principle it seems that there is more to consciousness than just behavior. What the real dividing line between the conscious and the non-conscious then is how the responses are generated. Are they generated by thoughts or are they generated by rote? Currently I am working on a theory that gives a criterion for dividing between the two, without resorting to examining their behavior, but I am reluctant to discuss it here since it is still a work in progress. Of course I am always willing to listen to reader suggestions.

* Admittedly the method might be more complicated than this, as it could be rule-following to generate the answers as well, but it would still fail the test because it does not have room to store an infinite number of rules. (A finite set of rules that would fool the interrogator is assumed to be a conscious mind, as such rules would need to express a complete phenomenal world in order to answer all questions without being infinite.)

** Another, less serious case, in which the Turing test fails to divide between the conscious and the non-conscious is when the subject refuses to answer. It is perfectly possible for a conscious subject to sit in silence, and a machine could be created that imitated this behavior perfectly without being conscious.

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