Here is the second premise of Argument #6 (the Kalam Cosmological Argument) in Peter Kreeft’s case for the existence of God, from Chapter 3 of his Handbook of Christian Apologetics (hereafter: HCA):

2. The universe began to exist. (HCA, p.58)

In order to be able to rationally determine whether this claim is true or false, we need to first understand what it means.

Based on a definition of “the universe” from Kreeft, plus some clarifications of that definition that were also provided by Kreeft, I understand this phrase as follows:

X is “the universe” IF AND ONLY IF:

X is the collection of all of the things that currently exist in both space and in time.

We can revise premise (2) in accordance with this understanding:

2a. The collection of all of the things that currently exist in both space and in time began to exist.

If (2a) is true, then (2) is true.  If (2a) is false, then (2) is false.  So, we need to determine whether (2a) is true or false.

Because we have clarified the meaning of this claim, it becomes fairly easy to evaluate this claim, and it is now clear to me that this claim is in fact TRUE.

THE COLLECTION OF ALL OF THE THINGS THAT CURRENTLY EXIST…

What is “The collection of all the things that currently exist in both space and in time”?

Well, basically, this is the collection of the currently existing GALAXIES:

Galaxy

    A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.[1][2] The word galaxy is derived from the Greek galaxias (γαλαξίας), literally “milky”, a reference to the Milky Way. Galaxies range in size from dwarfs with just a few hundred million (10⁸) stars to giants with one hundred trillion (10¹⁴) stars,[3] each orbiting its galaxy’s center of mass.

    Galaxies are categorized according to their visual morphology as elliptical,[4] spiral, or irregular.[5] Many galaxies are thought to have supermassive black holes at their active centers. The Milky Way’s central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun.[6] As of March 2016, GN-z11 is the oldest and most distant observed galaxy with a comoving distance of 32 billion light-years from Earth, and observed as it existed just 400 million years after the Big Bang.

    Recent estimates of the number of galaxies in the observable universe range from 200 billion (2×10¹¹)[7] to 2 trillion (2×10¹²) or more,[8][9] containing more stars than all the grains of sand on planet Earth.[10]

There is a little bit of gas between galaxies, but it is roughly correct to say that “The collection of all the things that currently exist in both space and in time” is “The collection of galaxies that currently exist.”  So, we can clarify the second premise a bit more:

2b. The collection of galaxies that currently exist began to exist.

Statement (2b) is clearly a true statement, and since (2b) is roughly equivalent to (2a), the fact that (2b) is clearly true, provides us with good reason to believe that (2a) is true, and if (2a) is true, then (2) is also true.  So, we have good reason to believe that premise (2) is true, assuming Kreeft’s definition of “the universe”.

Furthermore, although the galaxies that currently exist might not include absolutely everything that currently exists in both space and in time (because, for example, there is some gas between the galaxies), those galaxies (and the contents of those galaxies) clearly constitute MOST of the things that currently exist in both space and in time.  So, if those galaxies (and the contents of those galaxies) began to exist, then MOST of the things that currently exist in both space and in time began to exist, and thus “The collection of all the things that currently exist in both space and in time” began to exist, because that collection did NOT exist until those galaxies began to exist.

Based on current Big Bang astronomy,  stars did not begin to form until about 100 or 200 million years after the Big Bang.  So, for the first 100 million years after the Big Bang, there were no stars and no galaxies (or very few stars and galaxies).  The oldest galaxy that we know of formed about 400 million years after the Big Bang (see the quote above from an article on Galaxies). But stars and galaxies exist NOW, so the collection of currently existing galaxies BEGAN TO EXIST no earlier than about 400 million years after the Big Bang.  Clearly, premise (2b) is TRUE.

Did the collection of galaxies that currently exist begin to exist about 400 million years after the Big Bang?  Well at least ONE of the currently existing galaxies began to exist about 400 million years after the Big Bang.  But not all galaxies began to exist at the same time.

Our galaxy is the Milky Way Galaxy, and the nearest galaxy to ours is the Andromeda Galaxy.  The Andromeda Galaxy formed about 10 billions years ago (see article on the Andomeda Galaxy).  So, two of the currently existing galaxies are the Milky Way Galaxy and the Andromeda Galaxy.  Since the Andomeda Galaxy is one of the currently existing galaxies, “the collection” of currently existing galaxies did not exist, one might reasonably assert, until the Andromeda Galaxy was formed about 10 billion years ago.  In that case, “the collection of galaxies that currently exist” did NOT exist prior to about 10 billion years ago, so it did not begin to exist prior to 10 billion years ago.

Since there are between 200 billion and 2 trillion galaxies that currently exist, it seems likely that some of those galaxies came into existence after the Andromeda Galaxy, perhaps sometime in the last billion years.  If one of the currently existing galaxies was formed in the past billion years, then “the collection of galaxies that currently exist” BEGAN TO EXIST less than one billion years ago, it would seem.

But did “the collection of galaxies that currently exist” begin to exist only when the most recently formed galaxy began to exist?  Or could “the collection of galaxies that currently exist” begin to exist sometime before every single galaxy in that collection was formed? For example, someone might reasonably claim that “the collection of galaxies that currently exist” began to exist when the oldest galaxy (among currently existing galaxies) began to exist.  Since the oldest currently existing galaxy that we know of formed about 400 million years after the Big Bang, on this view “the collection of galaxies that currently exist” began to exist about 400 million years after the Big Bang.

We can see now that the phrase “began to exist” is somewhat VAGUE when we are talking about collections of things.  On the one hand, it is somewhat reasonable to say that “the collection of currently existing galaxies”  began to exist when the oldest galaxy in that collection began to exist, even though billions of other galaxies would develop over the course of the next three billion years.  On the other hand, it is also reasonable to say that “the collection of currently existing galaxies” began to exist when the most recent galaxy began to exist (perhaps 10 billion years ago, or maybe less than one billion years ago).

Because of the vagueness of the phrase “began to exist” it is not clear whether “the collection of currently existing galaxies” began to exist about 13 billion years ago (when the oldest known galaxy formed), or 10 billion years ago (when the Andromeda Galaxy formed), or less than one billion years ago (when the most recent galaxy formed).  But one thing is clear: the collection of currently existing galaxies began to exist no earlier than hundreds of millions of years AFTER the Big Bang.

REVISED VERSION OF PHASE 1 ARGUMENT

We can reformulate the Phase 1 Argument to conform with the clarifications that we have developed above:

1. Whatever begins to exist has a cause of its coming into being.

2b. The collection of galaxies that currently exist began to exist.

THEREFORE:

3b. The collection of galaxies that currently exist has a cause of its coming into being.

In this reformulation of the argument, we can clearly see two important points:

• Premise (2b) is clearly TRUE.
• The conclusion (3b) is clearly IRRELEVANT to the question “Does God exist?”

Why is the conclusion (3b) irrelevant to the existence of God?  We already have a fairly good scientific explanation for how the collection of galaxies that currently exist came into being, for how this collection of galaxies began to exist.

For one thing, we know that they did NOT come into existence from out of nothing.  First there was the Big Bang, and about 100 million years later stars began to develop, and about 400 million years after the Big Bang, the first galaxy (among those that still exist) developed.  For at least the next three billion years more and more stars and galaxies developed.  Astronomers and astrophysicists can provide evidence-based theories and explanations of how the billions of galaxies that currently exist began to exist, so we have no need of the hypothesis of God to explain this phenomenon.

One more conclusion that we can draw here is that Kreeft has FAILED to properly define the phrase “the universe”.  So, the clarified version of the Phase 1 Argument of the Kalam Cosmological Argument is based on a BAD definition of “the universe”.  But the phrase “the universe” is a key concept in this argument, and in order to present a solid proof or argument for God, one must provide clear definitions of the key concepts in the argument, so it is Kreeft’s responsibility to provide a GOOD definition of “the universe” and he has FAILED to do so.

CONCLUSION

Kreeft’s Argument #6 FAILS because without a definition of “the universe” the argument is too UNCLEAR to be rationally evaluated, but with Kreeft’s definition of “the universe” the argument is IRRELEVANT to the question at issue: “Does God exist?”.  Either way, Argument #6 FAILS.