Craig’s presentation of KCA in 1979 (in The Existence of God and The Beginning of the Universe) has the following structure:

I. The intermediate conclusion (the conclusion of his syllogistic argument) is stated in ambiguous language, ambiguous concerning whether there is AT LEAST ONE thing that caused the existence of the universe or EXACTLY ONE thing that caused the existence of the universe.

II. Only the WEAK interpretation of this intermediate conclusion can be validly inferred from the premises (i.e. the premises only imply that there is AT LEAST ONE thing that caused the existence of the universe).

III. Craig then shifts to using unambiguous language which assumes that there is EXACTLY ONE thing that caused the existence of the universe.

IV. Finally, Craig urges the identification of the ONE UNCAUSED CAUSE of the universe with God.

We find this same structure in Craig’s presentation of KCA in 1994 (in Reasonable Faith, the revised edition), and the  same structure occurs in Craig’s most recent presentation of KCA in 2015 (in Craig’s 2015  lecture on KCA at the University of Birmingham).  Thus, Craig has been commiting the fallacy of equivocation for nearly four decades (for 36 years to be precise).

Reasonable Faith (revised edition, 1994)

 I. The Intermediate conclusion is stated in ambiguous language.

In Reasonable Faith, Craig continues to state the conclusion of the syllogistic argument in ambiguous language:

1. Whatever begins to exist has a cause.

2.The universe began to exist.

3. Therefore, the universe has a cause.

(Reasonable Faith, p.92)

The intermediate conclusion (3) has at least two possible meanings:

3a. The universe has AT LEAST ONE cause.

3b. The universe has EXACTLY ONE cause.

Craig runs through the second phase of the argument in six paragraphs later in the book (p.116-117).  He initially re-iterates his ambiguous intermediate conclusion, and then infers another equally amgiguous intermediate conclusion (emphasis in CAPS added by me):

From the first premiss–that whatever begins to exist has a cause–and the second premiss–that the universe began to exist–it follows logically that THE UNIVERSE HAS A CAUSE.  This conclusion ought to stagger us, to fill us with awe, for it means that THE UNIVERSE WAS BROUGHT INTO EXISTENCE BY SOMETHING which is greater than and beyond it.

(Reasonable Faith, p.116)

II. Only the WEAK interpretation of this intermediate conclusion can be validly inferred from the premises (i.e. the premises only imply that there is AT LEAST ONE thing that caused the existence of the universe).

Nothing has changed in the 1994 version of KCA that would make Craig’s syllogism a valid argument for the intermediate conclusion that there is EXACTLY ONE cause of the universe.  It is clear that only the weaker conclusion follows validly (i.e that there is AT LEAST ONE cause of the universe).

III. Craig then shifts to using unambiguous language which assumes that there is EXACTLY ONE thing that caused the existence of the universe.

In the second paragraph of Craig’s wrap up of KCA, he immediately slides into unambiguous language about the quantity of causes of the universe (emphasis added by me):

But what is the nature of THIS FIRST CAUSE? It seems to me quite plausible that IT is a personal being WHO created the universe.   (Reasonable Faith, p.116)

Paragraph 3 starts off with an ambiguous statement of the intermediate conclusion, but then slides into unambigious language assuming that there is EXACTLY ONE thing that is the cause of the universe (emphasis added by me):

Consider the following puzzle: we’ve concluded that the beginning of the universe was the effect of A FIRST CAUSE.  By the nature of the case THAT COSMIC CAUSE cannot have any beginning of ITS existence nor any prior cause.  Nor can there have been any changes in THIS CAUSE, either in ITS nature or operations, prior to the beginning of the universe.  IT just exists changelessly without any beginning, and a finite time ago IT brought the universe into existence.  Now this is exceedingly odd.  THE CAUSE is in some sense eternal and yet the effect which is produced is not eternal… How can THE CAUSE exist without the effect?

(Reasonable Faith, p.116-117)

Craig continues to use the unambigious expression “the cause” in Paragraph 4 (emphasis added by me):

But this seems to imply that if THE CAUSE of the universe existed eternally, the universe would also have existed eternally.  And this we know to be false. (Reasonable Faith, p. 117)

Craig continues to use the unambigious expression “the cause” in Paragraph 5 (emphasis added by me):

One might say that THE CAUSE came to exist or changed in some way just prior to the first event.  But then THE CAUSE’S beginning or changing would be the first event, and we must ask all over again for ITS cause. … The question is: How can a first event come to exist if THE CAUSE of that event exists changelessly and eternally?  Why isn’t the effect as co-eternal as THE CAUSE?  (Reasonable Faith, p. 117)

At the beginning of Paragraph 6, Craig re-iterates the unambigious expression “the cause” (emphasis added by me):

It seems that there is only one way out of this dilemma, and that is to infer that THE CAUSE of the universe is a personal agent WHO chooses to create a universe in time. (Reasonable Faith, p.117)

IV. Finally, Craig urges the identification of the ONE UNCAUSED CAUSE of the universe with God.

In the middle of Paragraph 6, Craig introduces the terms “Creator” and “God” and relates them to the phrase “the cause” (emphasis added by me):

…a finite time ago A CREATOR endowed with free will could have willed to bring the world into being at that moment.  In this way, GOD could exist changelessly and eternally but choose to create the world in time.  By “choose” one need not mean that THE CREATOR changes HIS mind about the decision to create, but that HE freely and eternally intends to create a world with a beginning.  By exercising HIS causal power, HE therefore brings it about that a world with a beginning comes to exist.  So THE CAUSE is eternal, but the effect is not.  (p.117)

In Paragraph 6, Craig starts out claiming that THE CAUSE of the universe is a personal agent.  He then talks about A CREATOR, then slides into speaking of THE CREATOR, and he refers to THE CREATOR with the singular masculine pronoun HE, and masculine possessive HIS.  Craig also drops the word GOD along the way, but does not explicitly claim that THE CREATOR or THE CAUSE of the universe ought to be identified with GOD.

However, when Craig initially introduces KCA, he implies that the conclusion of KCA is that God exists:

…I find the kalam cosmological argument for a temporal cause of the universe to be one of the most plausible arguments for God’s existence.  (p.92)

So, the reader already knows what the ultimate conclusion of KCA is supposed to be: God exists.

In the next section of Reasonable Faith, Craig goes on to discuss the Fine Tuning argument, but in the very first sentence of that section, Craig refers back to what was supposedly shown by KCA:

The purely philosophical argument for the personhood of THE CAUSE of the origin of the universe receives powerful scientific confirmation from the observed fine-tuning of the universe, which bespeaks intelligent design.

(Reasonable Faith, p.118)

This is very similar to the wording of a conclusion Craig states on p. 117:  “the cause of the universe is a personal agent…”. And it is clear that Craig is suggesting that this ONE cause, this ONE personal agent,  be identified as THE CREATOR of the universe and as GOD.

Thus we see that in 1994, Craig was still commiting the fallacy of equivocation in his presentation of KCA, just as he did in his 1979 presentation of KCA, just as Aquinas did in his presentation of cosmological arguments for God nearly 800 years ago.