WLC on Time, Part 5: More Mathematical Misconceptions
After my last installment of this series, I had thought that I would be done critiquing Dr. William Lane Craig’s misunderstandings of the science and mathematics regarding time. After all, I’ve already shown that his arguments in support of the archaic Tensed Theory of Time are unfalsifiable, fallacious, ill-conceived, and self-contradictory. What more could there be for me to say? Well, in this week’s Reasonable Faith Podcast, Dr. Craig gifts me with more of his misconceptions about time. Starting at the 13:15 mark and lasting through the rest of the podcast, Dr. Craig addresses a question posed to him about the implications of the Tenseless Theory of Time on the theory of Evolution by Natural Selection, which the questioner refers to as “the holy grail of atheism.” I’ll note that this questioner doesn’t seem to realize that even a great many devout Christians completely accept the veracity of Evolution by Natural Selection, and that it is no more an “atheist” theory than is the Pythagorean Theorem. However, the particular implications on evolutionary biology will take a back seat, today, to the more general implications which Dr. Craig claims are made by the Tenseless Theory of Time. Specifically, Dr. Craig asserts that nothing actually changes over time, on the Tenseless Theory. Dr. Craig’s logic seems to be as follows:
- On the Tenseless Theory, all points in time– past, present, and future– are equally real.
- A spatial object which exists at point A in the past cannot be the same spatial object which exists at point B in the present or future, since they do not share the same properties.
- Therefore, no actual change occurs on the Tenseless Theory of Time.
Dr. Craig uses the example of a fireplace poker. At one end of the poker is a handle, and at the other end is a hooked point. We do not think of this poker as changing from a handle to a point, because the whole poker exists together. Unfortunately for Dr. Craig, his inability to comprehend mathematics has once again prevented him from seeing a fairly glaring and obvious problem with his analogy. The properties of the poker certainly do change from a handle to a point over the distance of its length! Change is a comparison of some measurable properties with respect to other measurable properties. Let me give an easier example to visualize what I mean.
Let’s imagine that we are dropping a ball into a pit which is 1000 meters deep. The graph in Figure 1 represents this action. The x-axis tells us the distance from the top of the pit in meters. The t-axis measures the passage of time in seconds. The blue curve is the ball. Every point along the blue curve is equally real– the point at t=0 is just as real as the point at t=10. Does that mean that the ball at t=0 is not the same ball as the one at t=10? Of course not. Dr. Craig is committing a fallacy of composition, here. Individual points in the ball’s trajectory are not the ball. The ball is the set of all points in its space-time trajectory. Let’s put this in math terms. The ball is represented by the curve, which has the function . The point lies on the curve, but this point is not the curve. Similarly, the point lies on the curve, but this point is not the curve. The curve is all of the points which satisfy its function. Mathematically, when we talk about “change over time,” we are comparing the different values of x which satisfy the function at given points in time. Similarly, when you are talking about your friend “Bob,” you are referring to an entity which encompasses a whole set of space-time coordinates. You aren’t specifically talking about the “Bob” that existed at precisely 12:34pm on June 16, 2014, GMT. So, when we say that a change in Bob has occurred over time (often colloquially shortened to just “Bob changed”) we mean that his properties at one given point in time are not the same as his properties in another given point in time. We’re not talking about two different Bob’s, because “Bob” refers to an entire set of points in space-time. William Lane Craig suffers from a terrible lack of comprehension, when it comes to mathematics. As such, he wildly misconstrues the implications which the Tenseless Theory of Time has on the concept of “change.” He seems completely locked into his archaic view, incapable of even attempting to treat time as a physical dimension. Dr. Craig has been researching the philosophy of time for quite a number of years, now. One would think that, in all that research, he might have taken a little bit of time to learn the mathematics necessary to competently discuss the subject.
Articles in this series:
- Part 1: Introduction to Time and Relativity
- Part 2: Einstein the Verificationist
- Part 3: Bell’s Theorem and the Cosmic Microwave Background
- Part 4: General Relativity
- Part 5: The Nature of Change
- Part 6: Did the Universe Begin?