The Argument from Motion (First Way):
Principle: The principle of motion, which states that all things in the world are in motion or changing.
Argument: Since everything in motion is set into motion by something else, there must be an initial unmoved mover (God) who started the chain of motion without being moved itself.
The Argument from Efficient Causes (Second Way):
Principle: The principle of causality, which asserts that everything has a cause.
Argument: Since every effect has a cause, there must be an uncaused first cause (God) that initiated the chain of causality, as an infinite regress of causes is impossible.
The Argument from Possibility and Necessity (Third Way):
Principle: The principle of contingency, which posits that some things exist contingently (they could exist or not exist).
Argument: Contingent beings exist, and their existence relies on something else. There must be a necessary being (God) that is self-existent and does not rely on anything else for its existence.
The Argument from Gradation of Being (Fourth Way):
Principle: The principle of gradation, which states that things in the world can be ranked in terms of their goodness, truth, and beauty.
Argument: Since there are varying degrees of goodness, truth, and beauty in the world, there must be a standard of maximum goodness, truth, and beauty (God) by which all other things are measured.
The Argument from Design (Fifth Way):
Principle: The principle of teleology, which suggests that there is purpose or design in the world.
Argument: The order, complexity, and purpose evident in the natural world indicate the existence of an intelligent and purposeful designer (God) who arranged and maintains this order.