The Reality of Time

This is the weekly Q & A blog post by our Research Professor in Philosophy, Dr. William Lane Craig.

Question

Dr. Craig,

You have played a vital role in my apologetic development, a long with other philosophers. I am puzzled by the fact that a lot of things are taken for granted although examining their legitimacy is the job of philosophy, thus I need to ask you, why do you believe in time in the first place? Isn't just an idea in our mind that helps us locate an event in relation to our experience? I do not get older because of time, but because of my biological development and entropic reality. These are physical constituents of the Universe that entail space and mass in a dynamical interaction. Moreover, the elements that shape events already exist in our universe, to say the time for x has not yet come, is strictly to say that the physical conditions for x to occur is not satisfied yet by the gathered factors. Can you help me identify what I could be missing here, please?

Guillermo

Nicaragua

Dr. William Lane Craig’s Response

Nice to get a question from someone with the same name as mine! Why do I believe in time? In a word, I experience time, and I have no defeater of the veridicality of that experience.

In my work on God and time, I argue at length for the reality of tensed time, which entails that time is real. I cannot think of any other belief which we have that is so fundamental and so powerfully warranted as the belief that time is real. Even the belief in the existence of the external world of physical objects can’t compare to it. For the external world is apprehended as a temporal world, but in addition to that we apprehend time in the inner life of the mind as we experience a temporal succession of states of consciousness. Even if I were a Boltzmann Brain with the illusion of a physical world about me, the experience of time would remain undiminished for me.

So I’ve argued that belief in the reality of tensed time is a properly basic belief grounded in our temporal experience. Here’s the argument as I state it:

Since premiss (2) is true by definition of “properly basic belief,” the premiss requiring defense is (1).

I offer several arguments in support of (1), pointing to such data as our experience of the presentness of our experiences, our differential attitudes toward the past and future, and our experience of temporal becoming. These examples show how basic, deeply ingrained, strongly held, and universal is our belief in the reality of tense and temporal becoming. On any view that time is unreal, we are all of us hopelessly mired in irrationality, prisoners to an illusion from which we are powerless to free ourselves. By contrast, if a tensed theory of time is correct, our experiences and beliefs are entirely rational and appropriate. Thus, insofar as we think that such experiences are justified, we should embrace a tensed theory of time.

It follows from the above argument that we are prima facie justified in holding our belief in the objective reality of the distinction between past, present, and future. Far from being controversial, such a conclusion could be accepted even by a proponent of a tenseless view of time. What he will argue is that our prima facie justification is defeated in some way. But by what? I argue that there are no successful defeaters, including McTaggart’s famous argument for time’s unreality, of such experiences. (By the way, almost nobody agrees with McTaggart’s argument: tensed and tenseless time theorists just fault it in different ways.)

You ask, “Isn't [time] just an idea in our mind that helps us locate an event in relation to our experience?” I see no reason to think so; but even if it were, as explained above, because that experience is tensed, any idea that locates us relative to that experience will give us a tensed, temporal location.

You say, “I do not get older because of time, but because of my biological development and entropic reality.” Well, yes and no. Time does not make your body run down and in that sense age. But everything in time is getting older in the sense that it has existed for a greater temporal duration than it used to, regardless of its physical appearance. As Sydney Shoemaker once showed in a famous article, even a universe frozen into immobility can still undergo temporal passage and so grow older over time.

You assert, “the elements that shape events already exist in our universe, to say the time for x has not yet come, is strictly to say that the physical conditions for x to occur is not satisfied yet by the gathered factors.” Your own statement implies the reality of tensed time, for this is implied by saying that the physical conditions for x are not satisfied YET. That is a temporal expression which serves to locate the physical events in relation to the present. Similarly, your statement that the elements which shape events exist ALREADY in the universe!

I think time is inescapable. The error of too many is to equate time with some physical quantity rather than take it to be a reality which we try to measure by means of physical mechanisms (clocks). As John Lucas memorably put it, time is what clocks are there to tell. That may be what you’re missing.