Logic obviously suggests some things based upon limited, unverifiable evidence. But what logic really tells us is that "the finite past" is an illogical construct. Cosmological arguments tend to presume a Big Bang beginning which renders them wishful and circular. "Eternity," being equally immune to thorough scientific inspection, is therefore equally illogical. We simply can't know what we'll never be able to see or measure. And that's fine by me. I'll take "I don't know" any day over appeals to magic and pure speculation.
The Big Bang theory, ultimately, has nothing to do with the cosmological argument. The notion that it does is a common and unfortunate misunderstanding.
Once again, the problem of existence is metaphysical, not scientific, and the imperatives of logic, mathematics and ontology precede and have primacy over science. An infinite regress of causation in time or being cannot be traversed to the present, and an actual infinite is an absurdity. The material realm of being began to exist in the finite past.
Excerpt from an article I wrote some years ago:
Islamic philosophers seized on Aristotle's terminology and related it to the eternally self-subsistent and wholly transcendent Creator of all other things that exist. They developed two distinct lines of the cosmological argument: (1) the impossibility of an infinite regress of causation, albeit in terms of contingency (the argument of a necessary existent) and (2) the impossibility of an infinite regress in time (the argument from the absurdities of an actual infinite). These are also referred to as the vertical and horizontal versions of the cosmological, respectively, and the ontological justification for both is the logical necessity of eternalism.
Ibn Sina (also known as Avicenna, 980–1037 A.D.) extrapolated the argument from contingency, which was further developed by Aquinas (1225–1274 A.D.).
The Christian theologian and early empiricist philosopher John Philoponus of the 5th Century was actually the first to argue from the impossibility of an infinite regress in
Against Aristotle wherein he not only refuted a temporally infinite universe but the credibility of Aristotelian cosmology concerning the composition of the lower heavens and celestial spheres. Following the arguments of Philoponus, Al-Kindi (801–873 A.D.) composed the first formal version of the horizontal cosmological: "Every being which begins has a cause for its beginning; now the world is a being which begins; therefore, it possesses a cause for its beginning."
(I don't remember when exactly, but I encountered an article written by someone who wrongfully attributes this formulation to Al-Ghazali. Al-Ghazali uses it, but it didn't originate with him.) Aristotle himself understood that an actual infinity is impossible; i.e., the physical universe couldn't be spatially infinite. Philoponus and Al-Kindi argued that precisely because the universe is divisible magnitude as Aristotle points out, nothing about the universe could be infinite. An infinite past would be an actual infinity. Absurdity! Hence, the universe necessarily began to exist in the finite past. Philoponus and Al-Kindi's primary interest was to evince why no divisible entity could possibly be the necessary existent and invited one to conclude that only an indivisible and, therefore, timelessly immaterial entity could be the necessary existent.
While Al-Ghazali (1058–1111 A.D.) wholeheartedly agreed, he was dissatisfied with the unnecessary ambiguity of the argument. Like Philoponus and Al-Kindi before him, he argued that the universe is composed of temporal phenomena preceded by other temporally-ordered phenomena, and given that an actual infinite is impossible, such a series of temporal phenomena cannot continue to infinity. Then Al-Ghazali brilliantly observed that not only must the universe have a timeless cause of its existence, but this timeless cause
must be a personal free agent; for if the cause of the universe's existence were impersonal, it would be operationally mechanical. This would mean that the cause could never exist sans its effect, as from eternity the sufficient causal conditions for the effect to occur are given.
As explained by Craig:
The only way for the cause to be timeless but for its effect to begin in time is for the cause to be a personal agent who freely chooses to bring about an effect without any antecedent determining conditions. Philosophers call this type of causation 'agent causation,' and because the agent is free, he can initiate new effects by freely bringing about conditions which were not previously present. . . . Similarly, a finite time ago a Creator endowed with free will could have freely brought the world into being at that moment. In this way, the Creator could exist changelessly and eternally but choose to create the world in time. So the cause is eternal, but the effect is not. Thus, we are brought, not merely to a transcendent cause of the universe, but to a Personal Creator.
Hence, Al-Ghazali appends the syllogism per his ontological analysis of the properties of the cause. Known today as the Kalam, it's
this version of the argument that came to the medieval Christian tradition through Bonaventure (1221–74 A.D.), and it's this version that's championed by Craig et al. today with the very same philosophical supports for the second (or pivotal) premise, albeit, as decisively supplemented by Al-Ghazali's personal-impersonal distinction. Craig et al. have since mathematically and analogously elaborated on the philosophical supports and formulated a syllogistic expression of Al-Ghazali's ontological analysis.
Note that neither of the main premises were ever changed. Of course, they were never changed! Alex's notion is conceptually absurd, and his chronology regarding the historical development of the Kalam is nonsensical. Only the philosophical support for the second premise, deduced from the first principles of metaphysics, was revised, and the first premise is a metaphysical axiom! Axioms don't require additional proof. They are proofs (or logical necessities) in and of themselves.
