source

Daniel Dennett (1942-)

While he himself is a confirmed compatibilist, even a determinist, in “On Giving Libertarians What They Say They Want,” Chapter 15 of his 1978 book Brainstorms, Daniel Dennett articulated the case for a two-stage model of free will better than any libertarian.
His “Valerian” model of decision making, named after the poet Paul Valéry, combines indeterminism to generate alternative possibilities, with (in our view, adequate) determinism to choose among the possibilities.

“The model of decision making I am proposing, has the following feature: when we are faced with an important decision, a consideration-generator whose output is to some degree undetermined produces a series of considerations, some of which may of course be immediately rejected as irrelevant by the agent (consciously or unconsciously). Those considerations that are selected by the agent as having a more than negligible bearing on the decision then figure in a reasoning process, and if the agent is in the main reasonable, those considerations ultimately serve as predictors and explicators of the agent’s final decision.” (Brainstorms, p.295)

Dennett gives six excellent reasons why this is the kind of free will that libertarians say they want. He says,
“First…The intelligent selection, rejection, and weighing of the considerations that do occur to the subject is a matter of intelligence making the difference.”
“Second, I think it installs indeterminism in the right place for the libertarian, if there is a right place at all.”
“Third…from the point of view of biological engineering, it is just more efficient and in the end more rational that decision making should occur in this way.”
“A fourth observation in favour of the model is that it permits moral education to make a difference, without making all of the difference.”
“Fifth – and I think this is perhaps the most important thing to be said in favour of this model – it provides some account of our important intuition that we are the authors of our moral decisions.”
“Finally, the model I propose points to the multiplicity of decisions that encircle our moral decisions and suggests that in many cases our ultimate decision as to which way to act is less important phenomenologically as a contributor to our sense of free will than the prior decisions affecting our deliberation process itself: the decision, for instance, not to consider any further, to terminate deliberation; or the decision to ignore certain lines of inquiry.”
“These prior and subsidiary decisions contribute, I think, to our sense of ourselves as responsible free agents, roughly in the following way: I am faced with an important decision to make, and after a certain amount of deliberation, I say to myself: “That’s enough. I’ve considered this matter enough and now I’m going to act,” in the full knowledge that I could have considered further, in the full knowledge that the eventualities may prove that I decided in error, but with the acceptance of responsibility in any case.” (p.295-7)

At times, Dennett seems pleased with his result.
“This result is not just what the libertarian is looking for, but it is a useful result nevertheless. It shows that we can indeed install indeterminism in the internal causal chains affecting human behavior at the macroscopic level while preserving the intelligibility of practical deliberation that the libertarian requires. We may have good reasons from other quarters for embracing determinism, but we need not fear that macroscopic indeterminism in human behavior would of necessity rob our lives of intelligibility by producing chaos.” (p.292)
“we need not fear that causal indeterminism would make our lives unintelligible.” (p.298)

“Even if one embraces the sort of view I have outlined, the deterministic view of the unbranching and inexorable history of the universe can inspire terror or despair, and perhaps the libertarian is right that there is no way to allay these feelings short of a brute denial of determinism. Perhaps such a denial, and only such a denial, would permit us to make sense of the notion that our actual lives are created by us over time out of possibilities that exist in virtue of our earlier decisions; that we trace a path through a branching maze that both defines who we are, and why, to some extent (if we are fortunate enough to maintain against all vicissitudes the integrity of our deliberational machinery) we are responsible for being who we are.” (p.299)

At other times, he is skeptical.
His model, he says, “installs indeterminism in the right place for the libertarian, if there is a right place at all.” and “it seems that all we have done is install indeterminism in a harmless place by installing it in an irrelevant place.” (p.295)
Dennett seems to be soliciting interest in the model – from libertarian quarters? It is unfortunate that libertarians did not accept and improve Dennett’s two-stage model. See What if Libertarians Had Accepted What Dan Dennett Gave Them in 1978?

If they had, the history of the free will problem would have been markedly different for the last thirty years, perhaps successfully reconciling indeterminism with free will, as the best two-stage models now do, just as Hume reconciled freedom with determinism.

“There may not be compelling grounds from this quarter for favoring an indeterministic vision of the springs of our action, but if considerations from other quarters favor indeterminism, we can at least be fairly sanguine about the prospects of incorporating indeterminism into our picture of deliberation, even if we cannot yet see what point such an incorporation would have.” (p.299)

The point of incorporating indeterminism is of course is to break the causal chain of pre-determinism, and to provide a source for novel ideas that were not already implicit in past events, thus explaining not only free will but creativity. This requires irreducible and ontological quantum indeterminacy.

But Dennett does not think that irreducible quantum randomness provides anything essential beyond the deterministic pseudo-random number generation of computer science.

“Isn’t it the case that the new improved proposed model for human deliberation can do as well with a random-but-deterministic generation process as with a causally undetermined process? Suppose that to the extent that the considerations that occur to me are unpredictable, they are unpredictable simply because they are fortuitously determined by some arbitrary and irrelevant factors, such as the location of the planets or what I had for breakfast.” (p.298)
With his strong background in computer science and artificial intelligence, it is no surprise that Dennett continues to seek a “computational” model of the mind. But man is not a machine and the mind is not a computer.
Dennett accepts the results of modern physics and does not deny the existence of quantum randomness. He calls himself a “naturalist” who wants to reconcile free will with natural science.

But what is “natural” about a computer-generated pseudo-random number sequence? The algorithm that generates it is quintessentially artificial. In the course of evolution, quantum mechanical randomness (along with the incredible quantum stability of information structures, without which no structures at all would exist) is naturally available to generate alternative possibilities.

Why would evolution need to create an algorithmic computational capability to generate those possibilities, when genuine and irreducible quantum randomness already provides them?

And who, before human computer designers, would be the author or artificer of the algorithm? Gregory Chaitin tells us that the information in a random-number sequence is only as much as is in the algorithm that created the sequence. And note that the artificial algorithm author implicitly has the kind of knowledge attributed to Laplace’s Demon.

Since Dennett is a confirmed atheist, it seems odd that he has the “antipathy to chance” described by William James that is characteristic of religious believers. Quantum randomness is far more atheistic than pseudo-randomness, with the latter’s implicit author or artificer.

Despite his qualms, Dennett seems to have located randomness in exactly the right place, the random generation of alternative considerations for his adequately determined selection process. In this first stage of free will, genuine quantum randomness (though not pseudo-randomness) breaks the causal chain of Laplacian determinism, without making the decisions themselves random.

Dennett on Austin’s Putt
In his 2003 book, Freedom Evolves, Daniel Dennett says that Austin’s Putt clarifies the mistaken fear that determinism reduces posibilities. Considering that Dennett is an actualist, who believes there is only one possible future, this bears close examination.
First, don’t miss the irony that Dennett is using “possible worlds” thinking, which makes the one world we are in only able to have one possible future, our actual world.

Dennett says

Now that we have a clearer understanding of possible worlds, we can expose three major confusions about possibility and causation that have bedeviled the quest for an account of free will. First is the fear that determinism reduces our possibilities. We can see why the claim seems to have merit by considering a famous example proposed many years ago by John Austin:
Consider the case where I miss a very short putt and kick myself because I could have holed it. It is not that I should have holed it if I had tried: I did try, and missed. It is not that I should have holed it if conditions had been different: that might of course be so, but I am talking about conditions as they precisely were, and asserting that I could have holed it. There is the rub. Nor does “I can hole it this time” mean that I shall hole it this time if I try or if anything else; for I may try and miss, and yet not be convinced that I could not have done it; indeed, further experiments may confirm my belief that I could have done it that time, although I did not. (Austin 1961, p. 166)
Austin didn’t hole the putt. Could he have, if determinism is true? The possible-worlds interpretation exposes the misstep in Austin’s thinking. First, suppose that determinism holds, and that Austin misses, and let H be the sentence “Austin holes the putt.” We now need to choose the set X of relevant possible worlds that we need to canvass to see whether he could have made it. Suppose X is chosen to be the set of physically possible worlds that are identical to the actual world at some time t0 prior to the putt. Since determinism says that there is at any instant exactly one physically possible future, this set of worlds has just one member, the actual world, the world in which Austin misses. So, choosing set X in this way, we get the result that H does not hold for any world in X. So it was not possible, on this reading, for Austin to hole the putt.
To include adjacent worlds seems to add alternative possibilities? Of course, this method of choosing X (call it the narrow method) is only one among many. Suppose we were to admit into X worlds that differ in a few imperceptibly microscopic ways from actuality at t0; we might well find that we’ve now included worlds in which Austin holes the putt, even when determinism obtains. This is, after all, what recent work on chaos has shown: Many phenomena of interest to us can change radically if one minutely alters the initial conditions. So the question is: When people contend that events are possible, are they really thinking in terms of the narrow method?

Suppose that Austin is an utterly incompetent golfer, and his partner in today’s foursome is inclined to deny that he could have made the putt. If we let X range too widely, we may include worlds in which Austin, thanks to years of expensive lessons, winds up a championship player who holes the putt easily. That is not what Austin is claiming, presumably. Austin seems to endorse the narrow method of choosing X when he insists that he is “talking about conditions as they precisely were.” Yet in the next sentence he seems to rescind this endorsement, observing that “further experiments may confirm my belief that I could have done it that time, although I did not.” What further experiments might indeed confirm Austin’s belief that he could have done it? Experiments on the putting green? Would his belief be shored up by his setting up and sinking near-duplicates of that short putt ten times in a row?

If this is the sort of experiment he has in mind, then he is not as interested as he claims he is in conditions as they precisely were. To see this, suppose instead that Austin’s “further experiments” consisted in taking out a box of matches and lighting ten in a row. “See,” he says, “I could have made that very putt.” We would rightly object that his experiments had absolutely no bearing on his claim. Sinking ten short putts would have no more bearing on his claim, understood in the narrow sense as a claim about “conditions as they precisely were.” We suggest that Austin would be content to consider “Austin holes the putt” possible if, in situations very similar to the actual occasion in question, he holes the putt. We think that this is what he meant, and that he would be right to think about his putt this way. This is the familiar, reasonable, useful way to conduct “further experiments” whenever we are interested in understanding the causation involved in a phenomenon of interest. We vary the initial conditions slightly (and often systematically) to see what changes and what stays the same. This is the way to gather useful information from the world to guide our further campaigns of avoidance and enhancement.

Curiously, this very point was made, at least obliquely, by G. E. Moore in the work Austin was criticizing in the passage quoted. Moore’s examples were simple: Cats can climb trees and dogs can’t, and a steamship that is now traveling at 25 knots can, of course, also steam at 20 knots (but not, of course, in precisely the circumstances it is now in, with the engine set at Full Speed Ahead). The sense of “can” invoked in these uncontroversial claims, the sense called “can (general)” by Honoré (1964) in an important but neglected article, is one that requires us to look not at “conditions as they precisely were” but at minor variations on those conditions.

So Austin equivocates when he discusses possibilities. In truth, the narrow method of choosing X does not have the significance that he and many others imagine. From this it follows that the truth or falsity of determinism should not affect our belief that certain unrealized events were nevertheless “possible,” in an important everyday sense of the word. We can bolster this last claim by paying a visit to a narrow domain in which we know with certainty that determinism reigns: the realm of chess-playing computer programs.