Summary
Everything that exists must have a reason for its existence. Every 'thing' that exists does so either due simply to its necessity (in which case, it could never not not exist) or some other thing external to it caused its existence. This rule extends all they way to the universe itself. Just as desks, chairs, paintings and people have reasons for existing, the universe must also have an explanation for its existence.Since the universe includes all physical reality, the explanation for the existence of the universe must originate from outside of the universe. It is this explanation that deists, theists and Christians call "God".
Class Notes
Suggested Reading
William Lane Craig has a lot of written material on the Argument From Contingency. Here are just two articles taken from his "Q&A" section from reasonablefaith.org:The first one is a basic overview of the argument.
The second is a more advanced article that refutes several objections put forth against the Argument from Contingency. If you are unversed in the field of philosophy, you may not understand all of this article because of the technical jargon. However, you can at least take heart that objections that are typically made against the Argument From Contingency have been refuted by professional philosophers with sound and reasoned answers.
But in the end, it is up to each individual person to think for themselves and come to a conclusion regardless of what anyone else thinks. We all must ask ourselves if we think an argument has valid, reasonable and plausible premises that allow us to accept the argument's conclusion or do we think there are objections that are more plausible than the argument's premises and thus allowing us to reject the argument's conclusion? We all have the free will to decide for ourselves but we should have rational and reasonable reasons for believing what we do, no matter how we decide.
