The Kalam Cosmological Argument

The Argument

Everything that begins to exist has a cause.
The universe began to exist.
Therefore, the universe has a cause.

Proponents then argue that this cause must possess specific attributes: it must be timeless (existing outside of time), spaceless (existing outside of space), immaterial (not composed of physical matter), incredibly powerful (capable of creating the universe), and personal (possessing agency to choose to create). These characteristics, they argue, align closely with traditional conceptions of God.

"The Kalam Cosmological Argument is a simple yet powerful argument that resonates with our common experience and intuition about causality and the origin of things."

William Lane Craig, "Reasonable Faith" (2008)

The Rebuttals

Definition of 'Universe': The argument may equivocate on the definition of 'universe'. It's unclear whether it refers to our observable universe, the totality of physical reality, or all of existence including potential multiverses.
Infinite Regress: If everything needs a cause, then what caused God? If God doesn't need a cause because He is eternal, why can't the same reasoning be applied to the universe or a multiverse?
Nature of Time: Some theories in physics, such as certain interpretations of Einstein's General Relativity, suggest that time itself began with the universe. If true, this would make the concept of a 'cause' problematic, as causality typically implies a temporal relationship.
Fallacy of Composition: Just because everything within the universe has a cause doesn't necessarily mean the universe itself needs a cause. This is akin to arguing that because every human has a mother, humanity as a whole must have a mother.

"Even if we grant that the universe has a cause, we are not justified in making any inferences about the nature of this cause, let alone identifying it with the God of classical theism."

Graham Oppy, "Arguing about Gods" (2006)