Everything in this world is always moving/changing eg. ice to water. Everything that moves/changes, does so by actualising potential. Aquinas says there can't be an infinite regress of movers/changers - the chain must have a beginning somewhere. So, there must be at least one thing that's different from all other links in the chain, something that can set off movement/change but doesn't need anything acting on it to make it move/change.
1.2 Second way (uncaused causer)
Nothing can be the cause of itself. This is because it would have to exist in order to bring itself into existence. Therefore, if we trace back far enough, there must be a first cause, caused by no other. This is what he understand as God.
1.3 Third way (possibility and necessity)
1) Everything in the world is contingent - everything in the world didn't cause itself to exist, and could not have existed. If everything at one time didn't exist there would have been nothing in existence now because nothing can cause its own existence. There must be something that doesn't need something to bring it to existence - a necessary being. 2) Two types of necessary being. Caused and uncaused necessary beings. Caused necessary = angels. Once they are caused they can't not exist. Uncaused necessary being = doesn't need anything to exist, but always has and always will. 3) An infinite regress is impossible. There exists some being have of itself its own necessity....causing in others their necessity. This is God.
2.1 Sufficient reason
This explains the existence of a thing and an explanation as to why its like that and not different. Russell and Copelston argued about the sufficient reason of the universe, as Copelston says it can only be sufficiently explained by reference to God.
2.2 His argument
1) There are at least some beings in the world that don't contain in themselves the reason fro their existence.
2) The totality of the world comprises such objects. There is no world distinct from these objects.
3) The explanation for the world must therefore be found externally to it.
4) The reason must ultimately be an existent being that contains within itself the reason for its own existence. That reason is that it cannot not exist, its a necessary being - God.
3 Hume's challenges
3.1 Rejection of the idea we cannot
know anything about cause
1) He viewed experience as the foundation of knowledge, but we haven't had experience of the worlds creation. Therefore we are unable to make any connections about the creation of the Universe.
3.2 Rejection of the idea of
moving from individual
causes to a cause for the
Wrong that you can say every event in the universe has a cause and therefore the Universe has a cause.
3.3 Rejection of the idea of a
beginning to the Universe
He suggested perhaps it's always existed. Modern cosmology does allow for an infinite past history of the Universe.
3.4 Rejection of the idea of the
Christian God as the
No reason to conclude that even if the Universe did have a cause, that the cause must be the Christian God. The cosmological argument tells us nothing about the attributes of the necessary being. He said it could be possible to have been a committee of Gods.
4 Russell's Challenges
4.1 Rejection of the principle of
Questioned the claim that there was a reason for everything. "The universe is just there and that is all."
4.2 Rejection of the idea of moving
from individual causes to a cause
for the totality
Like Hume, Russell rejected that you could make the move from saying that everything in the Universe has a cause and therefore the Universe itself has a cause.
"To say that every person who exists has a mother does not then imply that the human race must have a mother."
4.3 Rejection of the notion of a
The word necessary could not meaningfully be applied to things, only to analytic propositions. Therefore he rejected the notion of necessary being, and the idea that existence is a real predicate.