This is a slightly modified version of a post I made to an online discussion group.
Ayn Rand's views on causation contradict her views on free will. The reason is very simple: her
views on causation are those of a determinist; her views on free will, however, make her a
libertarian (as we will see below). And those two positions are, by definition, incompatible. But there is another serious mistake in Rand's theory of causation, one that is even worse because it is more fundamental.
Before proceeding, it might be a good idea to define the terms "determinism" and "libertarianism". Determinism is the view that the future is closed to all but one possibility, or, as Rand might have put it, that "everything in the future is already pre-set and inevitable" (The Ayn Rand Lexicon, 122). Libertarianism is the view that we have free will and that, since free will is incompatible with determinism, determinism is false. This is the standard meaning of libertarianism (see, e.g., Free Will, ed. Robert Kane, 17).
Rand is, in a sense, a determinist because of what she says regarding the relationship between causation and the laws of logic. Rand has the unusual view that the law of causation is a corollary of the law of identity. Thus, for her, it is necessarily true that everything has a cause. Leonard Peikoff explains the point as follows: "Every entity has a nature; ... it has certain attributes and no others. Such an entity must act in accordance with its nature. The only alternatives would be for an entity to act apart from its nature or against it; both of those are impossible. ... In any given set of circumstances, therefore, there is only one action possible to an entity, the action expressive of its identity. This is the action it will take, the action that is caused and necessitated by its nature." (Objectivism: the Philosophy of Ayn Rand, 14.)
Now, some Objectivists believe that Peikoff sometimes misrepresents Rand's views in this book
(which was written after Rand's death), but they cannot reasonably claim such a thing regarding the
above, for Peikoff made essentially the same point in "The Analytic-Synthetic Dichotomy", an article
that was personally approved by Rand:
"As far as metaphysical reality is concerned (omitting human actions from consideration, for the
moment), there are no 'facts which happen to be but could have been otherwise'... Since things are
what they are, since everything that exists possesses a specific identity, nothing in reality can
occur causelessly or by chance. The nature of an entity determines what it can do and, in any given
set of circumstances, dictates what it will do." (The Ayn Rand Lexicon, 333.)
The only important difference between the two passages is that in the latter Peikoff specifically
points out that this does not apply to human actions. We will return to this below. Apart from human
actions, however, Rand believed that every event was determined in the sense that, at any given
moment, only one outcome was possible nothing that happens could have happened otherwise. Peikoff uses the example of a helium-filled balloon to clarify the issue: if, under the same set of circumstances, it were possible for a balloon to act in more than one way if it could rise or fall then the law of identity would be violated. "Such incompatible outcomes would have to derive from incompatible (contradictory) aspects of the entity's nature. But there are no contradictory aspects. A is A." (Objectivism: the Philosophy of Ayn Rand, 14-15.) Objectivists often make this point in arguing against the standard interpretation of quantum
mechanics, which states that there are truly random events in the physical world.
According to Rand, then, the law of identity implies that everything has a cause, and this in turn implies that, at any given moment, there is only one way that anything can act only one outcome that is possible. This is causal determinism. A rather bizarre type of causal determinism, since it is based on nothing more than the law of identity, but causal determinism nonetheless.
But Rand also believes in freedom of the will, and believes that it is incompatible with determinism. In other words, she is a libertarian. Again, in Peikoff's Rand-approved words: "Because man has free will, no human choice and no phenomenon which is a product of human choice is metaphysically necessary. In regard to any man-made fact, it is valid to claim that man has chosen thus, but it was not inherent in the nature of existence for him to have done so: he could have done otherwise." (The Ayn Rand Lexicon, 180.) So when it comes to any man-made fact, it might not have been. Something else might have been instead. But this obviously contradicts what Peikoff said above regarding there being "in any given set of circumstances... only one action possible to an entity".
Now, as already pointed out, in "The Analytic-Synthetic Dichotomy", Peikoff explicitly leaves human action out of this determinist picture. It might therefore seem that there is
no contradiction: the deterministic view applies only to non-human reality. But this will not do unless Peikoff means that the law of identity does not apply to human beings. Remember that the whole point is that determinism (that is, that only one outcome is possible at any given time) is supposed to be entailed by that law of logic. On Rand's view, then, if a human being is free to either do A or not do A in a given situation, then the human being must not have a specific nature.
Of course, we all know that Rand did not really believe such a thing. She obviously believed that the law of identity applied to human beings as much as to anything else. But that's not my point. My point is that, if we accept what she says about the relationship between identity and causality, and also what she says about human volition, then we should conclude that human beings are exempt from the law of identity. And that is obviously ridiculous.
Objectivism attempts to avoid this contradiction by claiming that, in the case of human beings,
acting in accordance with one's nature does not imply that there is only one action possible at each
moment. It is part of human nature, according to Rand, to have the ability to choose from among
more than one course of action. "The attribute of volition", she says, "does not contradict the fact of identity... [Man] is able to initiate and direct his mental action only in accordance with the nature (the identity) of his consciousness." (Ibid.) Or in Peikoff's words: "The law of identity... tells us only that whatever entities there are, they act in accordance with their nature... The law of causality by itself, therefore, does not affirm or deny the reality of an irreducible choice. It says only this much: if such a choice does exist, then it, too, as a form of action, is performed and necessitated by an entity of a specific nature." (Objectivism: the Philosophy of Ayn Rand, 68-69.)
But this changes things. Now it no longer is the case that "acting in accordance with a specific
nature" implies that there is only one possible way of acting. According to Rand, human beings act in accordance with their nature, and thus in accordance with the law of identity, and yet they are able to choose from among more than one possible course of action. So the law of identity does not, in fact, mean that only one outcome is possible for an entity at any given time.
And in fact, that is exactly right: the original claim was simply wrong. Determinism (whether of human or non-human entities) simply does not follow from the law of identity. To suppose that it does, whether for human beings or for any other entity, is an obvious confusion. But now Rand's view of causation can be seen for what it really is: it means absolutely nothing. All Rand's "law of causation" tells us is that entities act in accordance with their nature. But that tells us nothing about how any given entity must act. It merely says that they act the way that they act.
John Hospers apparently pointed this out to Rand, saying that her claim that an entity must act
in accordance with its nature "is guaranteed by the meaning attached to the word 'nature'."
(Letters of Ayn Rand, 528.) Judging from her reply, she seems to not have understood the
complaint. His point, I take it, was that because her statement is true by definition, it is no more
than an empty truism. That every entity always acts in accordance with its nature tells us nothing about how it will in fact act, including whether or not there is more than one possible way for it to act. It does not, for instance, rule out the standard interpretation of quantum mechanics: all one needs to say is that it is in an electron's nature (for example) to behave unpredictably. Nor would it be contradicted by a helium-filled balloon that fell. If a balloon ever acted this way, then that would merely show that such behavior is part of its nature. Or, in other words, no matter how anything acts, it is by definition acting in accordance with its nature.
To sum up: Rand's view that the law of identity implies determinism contradicts her view that human beings have free will. Furthermore, it is simply false that determinism follows from the law of identity.