What happened to scientific determinism?

Review of Stephen Hawking’s “Brief Answers to the Big Questions” - Part 1

Determinism is a hugely important aspect of modern science. We call the laws of science “laws” because we assume they do not change. Therefore, once we know the circumstances of a situation with sufficient detail, we can, with the help of these laws, determine what is going to happen next.  For example, if we know the law of gravity, and the mass of two objects, we know exactly how they will move in relation to each other – whether one will fall on the other, or they will orbit each other, or just swing by each other once.

With that in mind, French scientist Pierre-Simon Laplace (1749 – 1827) postulated that, at least theoretically, everything could be pre-determined. Here is how Stephen Hawking, in his book “Brief Answers to Big Questions” paraphrased what Laplace said in this regard: “[I]f at one time we knew the positions and speeds of all the particles in the universe, then we would be able to calculate their behaviour at any other time in the past or future.” (90)

Then, Hawking comments: “I don’t think that Laplace was claiming that God didn’t exist. It is just that God doesn’t intervene to break the laws of science. That must be the position of every scientist.” (90, my emphasis) However, nowhere in the book does Hawking come up with a reason why this “must” be the position of “every” scientist.

It’s understandable why he says it though: Since the Enlightenment (a time and movement which Laplace was part of), determinism became the prime instrument with which philosophical materialists defended their view. Materialism, according to Wikipedia, holds that “matter is the fundamental substance in nature, and that all things, including mental states and consciousness, are results of material interactions. According to philosophical materialism, mind and consciousness are by-products or epiphenomena of material processes (such as the biochemistry of the human brain and nervous system), without which they cannot exist. This concept directly contrasts with idealism, where mind and consciousness are first-order realities to which matter is subject and material interactions are secondary.”

Materialism is hugely important to atheists, especially atheistic scientists. Here is what geneticist Richard Lewontin wrote in a review of a book by the famous science populariser Carl Sagan:

“We take the side of science in spite of the patent absurdity of some of its constructs, in spite of its failure to fulfil many of its extravagant promises of health and life, in spite of the tolerance of the scientific community for unsubstantiated just-so stories, because we have a prior commitment, a commitment to materialism. It is not that the methods and institutions of science somehow compel us to accept a material explanation of the phenomenal world, but, on the contrary, that we are forced by our a priori adherence to material causes to create an apparatus of investigation and a set of concepts that produce material explanations, no matter how counter-intuitive, no matter now mystifying to the uninitiated. Moreover, that materialism is an absolute, for we cannot allow a Divine Foot in the door.” (Quoted in: Mangalwadi, Vishal: The Book That Made Your World, Thomas Nelson, Nashville, Tennessee, 2011, p. 231; my emphasis.)

Hawking spends a large chunk of the book trying to save determinism. The reason: Currently, it appears to be broken. Hawking is quite open about this: “two developments … show that Laplace’s vision, of a complete prediction of the future, cannot be realised.” (91)

These two “developments”, or rather discoveries, are quantum mechanics and black holes. Quantum mechanics is the branch of physics that investigates sub-atomic particles. In the first half of the 20th century, it became clear to scientists that when looking at this microscopic level, they could precisely measure either the speed or the position of a particle, but, crucially, not both at the same time. That made it impossible to determine what a particle would do next. Black holes, on the other hand, are objects that are so dense that their gravitational force doesn’t even allow light to escape. For example large stars that have collapsed at the end of their life. That means we cannot see or measure what is happening inside.

Hawking is very imaginative when describing why this is a problem for materialist scientists:

“If information were really lost in black holes, we wouldn’t be able to predict the future, because a black hole could emit any collection of particles. It could emit a working television set or a leather-bound volume of the complete works of Shakespeare, though the chance of such exotic emissions is very low. It is much more likely to emit thermal radiation, like the glow from red-hot metal . . .  But it is a matter pf principle. If determinism, the predictability of the universe, breaks down with black holes, it could break down in other situations . . . Even worse, if determinism breaks down, we can’t be sure of our past history either. The history books and our memories could just be illusions.” (118/19)

Moreover, it’s not just dead stars turned into super-massive black holes, somewhere in the cosmic distance, that could suddenly emit something totally unpredictable. There is at least a theoretical possibility of mini black holes floating about which have yet to be detected. (116) They too, presumably, are a source of total unpredictability. 

Now here’s my thought: If scientists find no way to determine what comes when out of a black hole, and determinism remains elusive, then it is not only possible that a black hole suddenly emits TVs or leather-bound volumes. It is also possible that, with or without black holes, water can turn into wine, the sun may stop in its tracks, a bush can be on fire without burning to cinders, the blind can suddenly see and the lame walk. The dead might even rise again. It would also be possible that new species of plants and animals suddenly appear as if from nowhere.

That’s a conclusion Hawking shied away from, but it’s a logical consequence. But, like Lewontin, Hawking was a committed materialist, and he could not “allow a Divine Foot in the door”.

However, kudos is due to Hawking, because he at least has admitted, in a book popularising science, that there is a fundamental problem at the heart of modern, materialist science. That is more than most scientists are prepared to do.  

Next part of the review: In the beginning, Chance – or God?