3 Kinds of Cosmological Argument

According to William Lane Craig, there are three types of cosmological argument:

[i] That which argues against infinite regress (Aquinas)
[ii] That which argues that whatever begins must have a cause (‘Kalam’)
[iii] That which argues on the Principle of Sufficient Reason (Leibniz)

The cosmological argument of St Thomas Aquinas is contained in the first three of his ‘five ways’ (Summa Theologica); each of the three ways demonstrates that a infinite regress of (1) motion, (2) efficient causes and (3) contingent beings is not possible and that consequently, there must be an ‘Unmoved Mover’ and cause of the universe that exists per se.

The Kalam cosmological argument holds that (1) whatever begins to exist has a cause; (2) the universe began to exist; (3) the universe has a cause; there can not be an infinite temporal regress of causes because an actual temporal infinite is not possible;

According to Leibniz, the universe does not contain within itself a sufficient explanation for its own existence; therefore, we must look outside of the universe for an explanation.