The argument is made up as follows:
- Everything that begins to exist has an external cause.
- The universe began to exist.
- Therefore, the universe has an external cause.
If the first two premises above are true, then the conclusion must necessarily be true.
If either premise is false, however, then the conclusion must be false, as well.
Everything that begins to exist has an external cause
This premise is false if and only if there is something that begins to exist without an external cause, and this can only happen in two scenarios:
There is something that begins to exist with an internal cause
In other words, something creates itself.
This is impossible, because in order to create itself it must already exist, but in order to be created, it cannot exist. In other words, it must exist and not exist at the same time, and this violates the law of non-contradiction and is, therefore, logically impossible. Or to put it in symbolic notation, where p is existence, we would have,
This cannot be true, because the law of non-contradiction states this proposition is false:
This self-creation problem means that the scenario is false.
There is something that begins to exist without a cause
In other words, something is created by nothing.
This is also logically impossible, because nothing produces nothing or in Latin ex nihilo nihil fit. Nothing means “not anything” and, therefore, has no properties, and this includes the property to bring into existence or create anything.
The logical argument for the proposition that nothing produces nothing is as follows:
- If anything can begin to exist, then it is possible that anything exists.
- If not anything exists, then it is not possible that anything exists.
- If it is not possible that anything exists, then anything cannot begin to exist.
- Therefore, if not anything exists, anything cannot begin to exist or in other words, not anything cannot bring into existence anything.
- Not anything is nothing.
- Therefore, nothing cannot bring into existence anything.
- Therefore, ex nihilo nihil fit.