October 04, 2010
Hawking and Mlodinow: Philosophical Undertakers
Hi Dr Craig
Can you give your response to the following from Stephen Hawking who is quoted from his new book as saying, "Because there is a law such as gravity, the universe can and will create itself from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist," and "It is not necessary to invoke God to light the blue touch paper and set the universe going,"
If there is such a revolution in theistic philosophy, such as arguments for the origin of the universe as you maintain, how can physicists make these statements? Doesn't this show that theistic arguments don't hold much weight with current paradigm in physics?
Your question is just one of many such questions we’ve recently received concerning Stephen Hawking and Leonard Mlodinow’s new book The Grand Design. In Question of the Week #180 I addressed the implications of their theories for the kalam cosmological argument and the fine tuning argument for a Creator and Designer of the universe. Here I want to use your question, Matthew, “If there is such a revolution in theistic philosophy, such as arguments for the origin of the universe as you maintain, how can physicists make these statements?” as a springboard for addressing an underlying issue raised in the book.
Hawking and Mlodinow open The Grand Design with a series of profound philosophical questions: What is the nature of reality? Where did all this come from? Did the universe need a creator? Then they say this:
Traditionally these are questions for philosophy, but philosophy is dead. Philosophy has not kept up with modern developments in science, particularly physics. Scientists have become the bearers of the torch of discovery in our quest for knowledge (p. 5).
The professional philosopher can only roll his eyes at the effrontery and condescension of such a statement. Two scientists who have, to all appearances, little acquaintance with philosophy are prepared to pronounce an entire discipline dead and to insult their own faculty colleagues in philosophy at Cal Tech and Cambridge University, many of whom, like Michael Redhead and D. H. Mellor, are eminent philosophers of science, for supposedly failing to keep up. I couldn’t help but wonder what evidence our intrepid authors have of Mr. Redhead’s laggard scholarship? What recent works in philosophy have they read that form the basis for their verdict? Alas, they do not say.
The professional philosopher will regard their verdict as not merely condescending but also as outrageously naïve. The man who claims to have no need of philosophy is the one most apt to be fooled by it. One might therefore anticipate that Mlodinow and Hawking’s subsequent exposition of their favored theories will be underpinned by a host of unexamined philosophical presuppositions. That expectation is, in fact, borne out. Like their claims about the origin of the universe from “nothing” or about the Many Worlds Hypothesis to explain fine tuning, their claims about laws of nature, the possibility of miracles, scientific determinism, and the illusion of free will are asserted with only the thinnest of justification and little understanding of the philosophical issues involved.
Take, for example, their ruminations on laws of nature (pp. 27-34). After admitting the philosophical difficulty of defining just what a law of nature is, they proceed to ask three questions about natural laws: (i) What is the origin of the laws? (ii) Are there any exceptions to the laws, that is, miracles? (iii) Is there only one set of possible laws?
With respect to (i) they note that the traditional answer is that God established nature’s laws. But Hawking and Mlodinow complain than unless one invests God with certain attributes, this answer amounts no more than defining God as the embodiment of the laws of nature. I find this complaint perplexing. Since the classical theists they have in mind (including Descartes, whose views they misrepresent) thought that nature’s laws were freely willed by God, God could not be just the embodiment of those laws, since God could have established quite different laws. What Mlodinow and Hawking are describing is the view of Spinoza, a pantheist who regarded “God” and “nature” as synonyms. Of course, classical theists regarded God as having certain attributes, which distinguished Him from nature; that is simply entailed in the answer that God established the laws.
Hawking and Mlodinow seem prepared to acknowledge the coherence of this answer, but they think the “real crunch” then comes with (ii): Are there miracles? Hawking and Mlodinow apparently think that answering (ii) negatively casts doubt on a theistic answer to (i). If so, this claim is baffling. Suppose one is a Deist who thinks that God, having established the clockwork universe, chooses not to intervene in it? In that case, there is no “crunch” at all in answering (i) by “God” and (ii) by “No.”
In any case, why answer (ii) negatively? Incredibly, Hawking and Mlodinow think that science requires it:
The scientific determinism that Laplace formulated is the modern scientist’s answer to question two. It is, in fact, the basis of all modern science, and a principle that is important throughout this book. A scientific law is not a scientific law if it holds only when some supernatural being decides not to intervene (p. 30).
This argument is multiply confused. First, it is false that Laplacean determinism is the basis of modern science. Never mind the hordes of theistic scientists who affirm the reality of miracles; there are plenty of scientists, including Hawking and Mlodinow themselves (p. 72), who regard the indeterminism characteristic of quantum physics as ontic, not merely epistemic. If nature itself is indeterministic, then the determinism of Laplace, a Newtonian, does not hold. Even a complete set of nature’s laws will not fully determine the future. It’s easy to imagine all sorts of ways in which indeterminacy on the quantum level can be amplified so as to issue in macroscopic changes in the world. (I recall the amusing illustration of a grad student who is delayed in leaving the lab while waiting for the decay of a radioactive isotope and who as a result meets a girl in the hallway whom he falls in love with and eventually marries!) It’s puzzling that Hawking and Mlodinow are oblivious to the contradiction between their affirmation of both Laplacean determinism and quantum indeterminacy.
Second, Hawking and Mlodinow confuse determinism with naturalism. Quantum indeterminacy is the proof positive that modern science is not based on determinism. Their argument against the intervention of a supernatural being is an argument for naturalism, not determinism. Quantum indeterminacy is acceptable because it is naturalistic, whereas miracles involve supernatural agency. But then their claim that scientific laws would not be laws if they hold only when a supernatural being decides not to intervene is clearly false. The laws of nature describe the behavior of physical systems in the absence of any supernatural intervention. Were a supernatural agent to intervene, the predictions based on the laws would not hold precisely because non-natural factors, not envisioned by the laws, have entered the picture. The laws thus have implicit ceteris paribus conditions: they describe the behavior of physical systems given that no supernatural agent intervenes. If such a being does intervene, the natural law is not abrogated, since it describes the behavior of the system only under the assumption that such a being does not intervene.
Perhaps what Hawking and Mlodinow really mean to say is that science must presuppose naturalism in order to be a viable enterprise. But in that case, they have failed to distinguish methodological naturalism from metaphysical naturalism. Their argument at best would show that science is methodologically committed to entertaining only hypotheses positing natural causes; but that would do nothing to justify a negative answer to (ii), that there are no miracles. And even the question of science’s commitment to methodological naturalism is not itself a scientific question but a philosophical question about the nature of science.
Hawking and Mlodinow plunge into still deeper philosophical waters when they proceed to argue that because people live in the universe and interact with other objects in it “scientific determinism must hold for people as well” (p. 30). Therefore, “we are no more than biological machines and . . . free will is just an illusion” (p. 32). This is very weak. I see no reason to think that a creature endowed with freedom of the will could not exist spatio-temporally and act upon and be acted upon by other objects; so what’s the argument against such a thing? Hawking and Mlodinow ask, “If we have free will, where in the evolutionary tree did it develop?” If this is supposed to be an argument, there are at least two things wrong with it. First, my having free will does not depend upon my being able to specify where in the evolutionary process organisms first acquired it. Second, free will presumably arose as soon as the human brain evolved sufficient complexity to support self-conscious, rational reflection. So what’s the problem?
Mlodinow and Hawking also argue that free will is illusory because neurosurgeons can stimulate a person’s brain in such a way as to create the desire to move his limbs or lips. The fallacy here is thinking that because one can intervene to deterministically produce an effect, therefore the effect occurs deterministically in the absence of such intervention. Just because a neurosurgeon can stimulate my brain to make me want to move my arm obviously does not imply that on other occasions I do not or cannot move my arm freely.
Those are the only arguments for determinism that Mlodinow and Hawking present, and they do not consider any of the arguments against determinism. I wonder, for example, why they think that anything they’ve said in their book is true, since, on their view, they were determined to write it. Everything they say is the product of blind physical causes, like water’s gushing from a pipe or a tree’s growing a branch. What confidence can they have that anything they have said is true—including their assertion that determinism is true?
Mlodinow and Hawking reserve discussion of question (iii) about the uniqueness of nature’s laws until their treatment of the design argument from the fine-tuning of the universe for intelligent life. Since I commented on their discussion of (iii) last week, I’ll refrain from repeating myself here. But I trust that it is clear that, as one might expect, Mlodinow and Hawking are up to their necks in philosophical questions.
What one might not expect is that, after pronouncing the death of philosophy, Hawking and Mlodinow should themselves jump immediately into a philosophical discussion of scientific realism vs. anti-realism! The first third of their book is not about current scientific theories at all but is a disquisition on the history and philosophy of science. I found this section to be the most interesting and mind-boggling of the whole book.
Let me explain. Having set aside a Monday afternoon to read Hawking and Mlodinow’s book, I spent that morning working through a scholarly article from Blackwell’s Contemporary Debates in Metaphysics on a philosophical viewpoint known as ontological pluralism. Ontological pluralism is a view in a sub-discipline of philosophy whose name sounds like stuttering: meta-metaphysics, or, as it’s sometimes called, meta-ontology. This is philosophy at its most ethereal. Ontology is the study of being or of what exists, the nature of reality. Meta-ontology is one notch higher: it inquires whether ontological disputes are meaningful and how best to resolve them.
Ontological pluralism holds that there really is no right answer to many ontological questions (such as, “Do composite objects exist?”). According to the ontological pluralist there are just different ways of describing reality, and none of these is more correct or accurate than another. There literally is no fact of the matter at all in answer to these questions. So if you were to ask, “Is there such a thing as the Moon?,” the ontological pluralist would say that the question has no objective answer. It’s not true that the Moon exists, and it’s not true that the Moon does not exist. There just is no fact of the matter about whether there is such a thing as the Moon. Ontological pluralism is thus a radical view which is defended by a handful of philosophers.
Imagine my utter astonishment therefore to find Hawking and Mlodinow espousing ontological pluralism (without being aware of the name) as their philosophy of science! They call their view “model-dependent realism.” Their view is actually even more radical than ontological pluralism, for Hawking and Mlodinow take it to hold, not merely for high-level ontological disputes, but for our entire apprehension of the world. They explain,
. . . our brains interpret the input from our sensory organs by making a model of the world. When such a model is successful at explaining events, we tend to attribute to it, and to the elements and concepts that constitute it, the quality of reality or absolute truth. But there may be different ways in which one could model the same physical situation, with each employing different fundamental elements and concepts. If two such physical theories or models accurately predict the same events, one cannot be said to be more real than the other; rather, we are free to use which ever model is most convenient (p. 7).
On this view a model seems to be an (at least in part) unconscious way of organizing sense perceptions, which can be refined by scientific theorizing. We never come to know the way the world is; all we achieve are more or less convenient ways of organizing our perceptions. Such scepticism would be bad enough; but the situation is even worse. For these various models are not, even unbeknownst to us, more or less accurate approximations of reality. Rather there is no objective reality to which our models more or less accurately correspond. This is full blown ontological pluralism.
Mlodinow and Hawking are thus extreme anti-realists. Now they try to distinguish their view from scientific anti-realism by defining the latter as the view that “observation and experiment are meaningful but that theories are no more than useful instruments that do not embody any deeper truths underlying the observed phenomena” (p. 44). What Hawking and Mlodinow are describing here, however, is not scientific anti-realism but positivism, a philosophy of science popular in the 1930s and ’40s. Positivism proved to be untenable in part because of its artificial distinction between observation statements and theoretical statements. But anti-realism does not depend on positivism. Hawking and Mlodinow are more anti-realist than the positivists, for they not only deny that theoretical statements express objective truths about the world, but they deny this of observation statements as well, since even observation is model-dependent. Again, what they’re denying is not just knowledge of the way the world is, but that there even is an objective world to be known.
Just how serious they are about their anti-realism is evident from their examples. If a goldfish viewing the world through a curved bowl could formulate a model that enabled it to make successful predictions, then “we would have to admit the goldfish’s view as a valid picture of reality” (p. 39). Ptolemy’s geocentric model of the world was just as adequate as Copernicus’ heliocentric model. “So which is real, the Ptolemaic or Copernican system? Although it is not uncommon for people to say that Copernicus proved Ptolemy wrong, that is not true” (p. 41). This point is not that Copernicus’ evidence was insufficient, but that neither theory is objectively true. Contrasting young earth creationism and the big bang theory, Hawking and Mlodinow claim that while the big bang theory is “more useful,” nevertheless, “neither model can be said to be more real than the other” (p. 51)!
One cannot help but wonder what sort of argument would justify adopting so radical an ontological pluralism. All that Mlodinow and Hawking have to offer is the fact that if we were, say, inhabitants of a virtual reality controlled by alien beings, then there would be no way for us to tell that we were in the simulated world and so would have no reason to doubt its reality (p. 42). The trouble with this sort of argument is that it does not exclude the possibility that we have in such a case two competing theories of the world, one the aliens’ and one ours, and one of the theories is true and one false, even if we cannot tell which is which.
Moreover, the fact that our observations are model-dependent or theory-laden doesn’t imply that we cannot have knowledge of the way the world is (much less that there is no way the world is!). For example, a layman entering a scientific laboratory might see that there is a piece of machinery on the lab table, but he would not see that there is an interferometer on the lab table, since he lacks the theoretical knowledge to recognize it as such. A caveman entering the laboratory would not even see that there is a piece of machinery on the table, since he lacks the concept of a machine. But that does nothing to undermine the objective truth of the lab technician’s observation that there is an interferometer on the table.
Mlodinow and Hawking, not content with ontological pluralism, really go off the deep end when they assert, “There is no model-independent test of reality. It follows that a well-constructed model creates a reality of its own” (p. 172). This is an assertion of ontological relativity, the view that reality itself is different for persons having different models. If you are Fred Hoyle, the universe really has existed eternally in a steady state; but if you are Stephen Hawking the universe really began with a big bang. If you are the ancient physician Galen blood really does not circulate through the human body, but if you are William Harvey, it does! Such a view seems crazy and is made only more so by Mlodinow and Hawking’s claim that the model itself is responsible for creating its respective reality. It hardly needs to be said that no such conclusion follows from there being no model-independent test of the way the world is.
Whatever verdict we make on their arguments, the point is that despite their claim to speak as scientific torchbearers of knowledge, what Hawking and Mlodinow are engaged in is philosophy. The most important conclusions drawn in their book are philosophical, not scientific. Why, then, do they pronounce philosophy dead and claim as scientists to be bearing the torch of discovery? Simply because that enables them to cloak their amateurish philosophizing with the mantle of scientific authority and so avoid the hard work of actually arguing for, rather than merely asserting, their philosophical viewpoints.
The answer to your question, Matthew, was given long ago by Albert Einstein, when he remarked, “The man of science is a poor philosopher.” Hawking and Mlodinow’s book bears witness to Einstein’s sagacity.