From the book "Freedom and Determinism"
Topics in Contemporary Philosophy, Bradford Books Series
Cambridge, Massachusetts Institute of Technology, ©2004
Freedom and Determinism: A Framework
Authors : Joseph Keim Campbell, Michael O'Rourke, and David Shier
Thoughts about freedom and determinism have engaged philosophers since the days of ancient Greece. On the one hand, we generally regard ourselves as free and autonomous beings who are responsible for the actions that we perform. But this idea of ourselves appears to conflict with a variety of attitudes that we also have about the inevitable workings of the world around us. For instance, some people believe that strict, universal laws of nature govern the world. Others think that there is an omnipotent God who is the ultimate cause of all things. These more global views suggest that each particular event —including each human action— is causally necessitated, and so they suggest a conflict with the claim that we are free. Hence, the problem of freedom and determinism is, at base, a problem about reconciling attitudes we have toward ourselves with our more general thoughts about the world around us. It is a problem about locating our actions within those streams of events that make up the broader universe.
Freedom is usually discussed within the context of theoretical concerns about the nature of moral responsibility. For it is a basic assumption that some kind of freedom —call it "moral freedom"— is a necessary precondition for our being accountable for our actions. Moreover, even those who endorse moral nihilism, the claim that no one is ever morally responsible for anything, usually do so because they also believe that we lack moral freedom. Consequently, the assumption of freedom plays a role in our beliefs about the appropriateness of moral praise and blame. We find it absurd to blame a rock that happens to crash through our living room window but acceptable to blame the child who threw the rock. And we would consider such blame more legitimate were the rock knowingly and intentionally thrown by an adult with normal cognitive capacities. In trying to uncover the basis for these differences in attitude, we encounter other, more fundamental distinctions in moral psychology between action and passion, belief and desire, reason and emotion, and control and compulsion. Not surprisingly persons in the fields of ethics, philosophy of psychology, and philosophy of law all share an interest in understanding the nature of moral freedom. This remains true for moral nihilists since some understanding of the nature of moral freedom is implicit in its denial.
There are a variety of kinds of determinism that have been offered as potential threats to our freedom. For instance, there is logical determinism, the view that all propositions —including those reporting our future actions— are either true or false. There is also theological determinism, according to which an omniscient God knows about the future in complete detail. T. S. Eliot (1943) notes a problem between freedom and temporal determinism, which claims that time is another dimension like any of the other three spatial dimensions, so that the difference between what is in your past and what is in your future is a lot like the difference between what is to your left and what is to your right. Lastly, there is causal determinism, which claims that the past facts, together with the laws of nature, entail all future facts. Each of these determinisms is a global thesis, making a claim about all propositions. It is then suggested that this global property carries with it the kind of necessity that is itself a threat to our freedom.
Of course, the term 'freedom' is also ambiguous. There is political freedom and freedom of religion. These and other freedoms are characterized in a negative way, as the absence of certain constraints on one's activities or beliefs. Since there are many kinds of constraints, there are many negative freedoms. But the kind of freedom that metaphysicians are interested in —call it 'metaphysical freedom'— can also be described in a positive way, as an active power to do things that are up to us. In this sense, metaphysical freedom seems more fundamental than the other, merely negative freedoms. Metaphysical freedom may be even more fundamental than moral freedom, for as the problems noted in the previous paragraph indicate, threats to our freedom can be presented without mentioning attributions of moral praise or blame. On the other hand, each of the determinisms noted above is also a potential threat to our moral freedom. By and large, folks in the twentieth century are concerned with moral freedom —the freedom-relevant condition necessary for moral responsibility— and causal determinism.
For this reason, debates about freedom and determinism center on a set of distinct, though related, questions.
1. What is the thesis of causal determinism?
2. What is the nature of moral freedom?
3. Is moral freedom compatible with causal determinism?
4. Is causal determinism true?
5. Are any persons morally free?
The first three questions are conceptual and, thus, the primary focus of philosophers is directed towards answering those questions. A provisional answer to (1) was given above, but more precisely, determinism is the conjunction of the following two theses:
• For every instant of time, there is a proposition that expresses the state of the world at that instant;
• If p and q are any propositions that express the state of the world at some instants, then the conjunction of p with the laws of nature entails q. (van Inwagen 1983, 65)
Note that there are no temporal restrictions on p and q. Still if p is a proposition that expresses the state of the world at some time in the past, then when conjoined with the laws of nature it entails each and every future fact.
Until recently, all parties in the freedom and determinism debate accepted a short answer to (2), regarding the nature of moral freedom. First, it was held that the kind of freedom required for moral responsibility was free will. Second, it was accepted that free will requires that persons have alternatives to at least some of their actions, where a person S has an alternative to an action if S can do otherwise, or if S is able to do otherwise, or if it is within S's power to do otherwise. Call the identification of moral freedom with free will, the 'traditional view' of moral freedom.
[…]
Many standard ways of treating the problem of freedom and determinism presume answers to questions (1) and (4) above. As it turns out, it is not easy to say what it would be for the world to be deterministic, and even less easy to see whether, on any plausible account of what determinism amounts to, the world is in fact deterministic. In "Determinism: What We Have Learned and What We Still Don't Know," John Earman briefly reviews relevant parts of current physics with respect to their compatibility with determinism. He begins by distinguishing between determinism and prediction. While the latter may entail the former, the converse is false. Hence, one cannot infer from an inability to predict future states of a system that the time evolution of the system is indeterministic. Earman's review covers determinism and predictability not only of quantum systems, but also classical and relativistic systems. One of the interesting results he reaches is that, contrary to naive intuition, classical Newtonian physics is more hostile to determinism than either quantum mechanics or special relativity. Another is that the prospects for a deterministic theory unifying general relativity and quantum theory are rather grim. After noting various points of tension between determinism and each of these parts of current theory, Earman identifies ways in which extensions of the theories might save determinism, but argues that, as things now stand, questions about the truth or falsity of determinism remain open.
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