Welcome to Defenders, the teaching class of Dr. William Lane Craig, today an excurses on natural theology.

For more resources from Dr. Craig, go to reasonable faith.org.

In our lesson, we've been looking at the first scientific confirmation of the second premise

of the Kalam cosmological argument that the universe began to exist.

And that confirmation comes from the expansion of the universe.

And we saw last time that based upon the physical evidence, space and time can be

represented geometrically as a cone which shrinks as one goes back in time until one reaches an absolute beginning of the universe.

So that the standard Big Bang model predicts a beginning of the universe.

And although the standard model will need to be modified in various ways,

especially to accommodate a quantum gravity theory to explain the earliest split second of the

universe, nevertheless, a prediction of the standard model of a beginning of the universe has

now stood for nearly 100 years and remains the most probable account for the origin of the

universe.

And I concluded last time by saying in a sense the history of 20th century cosmology can be seen

as a series of failed attempts to avoid

the absolute beginning of the universe predicted by the standard model.

We've seen theories like the steady state model, oscillating models, vacuum fluctuation

models, eternal inflationary models, and so on and so forth, come and go.

And any model that doesn't involve an absolute beginning of the universe has shown to be untenable in some way.

So when someone like Sean Carroll in our debate on the evidence of cosmology for the existence

of the universe simply gives a list of beginningless models of the universe, that says nothing

about the tenability of those models.

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