what is aquinas’ third way
contingency
proof of 3rd way
p1= we observe that there are contingent beings
p2= a series of contingent beings cannot regress infinitely into the past
c1= if so, a series of contingent beings must be finite
p3= if this finite series was all that existed, then before it would be nothing
p4= if there was once nothing, there would be nothing now, which is incorrect
c2= so, there must be more than this finite series of contingent beings i.e. a necessary being
p5= there cannot be an infinite regress or necessary beings
c3= there must be a necessary being having got itself its own necessity, that thing is what we call god
wtf is aquinas saying??
he is arguing that we can agree that everything in the universe is contingent
contingent things need something else to bring them into existence, so nothing would have ever started.
there would still be nothing- unless there is some other being, capable of bringing other things into existence but being independent of everything else, or ‘necessary’
it would have to be a being which is not caused, and which depends on nothing else to continue to exist- and this, aquinas thought, would be god
what does leibniz base his argument on + what method of argument does he use
improves on Aquinas’ 3rd way by removing unnecessary reasoning about nothing once existence
leibniz bases his argument on the principle of sufficient reason, which does both the job of a causal principle and an argument against infinite regress
it shows there must be not just any causal explanation, but a causal explanation, but a causal explanation which provides an ultimately sufficient reason for everything that exists
this strengthens the argument by making it dependent on only one claim
a priori
proof of leibniz’ principle of sufficient reason
p1= for every true fact or assertion, there is a sufficient reason why it is thus and not otherwise
p2= there are two types of truth: truths of reasoning and truths of fact
p3a= truths of reasoning are necessary, so their opposite is impossible, the sufficient reason for truths of reasoning can be discovered a priori
p3b= truths of fact are contingent, so their opposite is possible. the sufficient reason for truths of fact cannot be discovered through other contingent truths, because they too require a sufficient explanation, and so on
c1= a sufficient reason for contingent facts must be found outside a series of contingent things
c2= the sufficient reason for contingent facts must be a necessary substance
c3= that necessary substance is god → god must exist
what is leibniz saying
claims that the principle of sufficient reason can be known as a necessary truth
even if we can’t know or even find out what the reason is, there must be one
‘from nothing nothing comes’ bc nothing is not sufficient to create something
only a necessary being is sufficient to explain the universe bc otherwise there would be an infinite regress of contingent beings, but an infinite regress alone can have no sufficient explanation
if things have always existed going back 4ever then nothing would have a sufficient reason for its existence
everything’s reason for existence would consist something for which its reason for existence consists in something else
there would simply be an infinite deferring of the reason for existence and thus would not actually be a reason for existence
so, a necessary being must have begun the chain of contingent beings and is the sufficient explanation of the universe
what is the kalam argument
infers a beginning cause rather than a sustaining cause
the causal sequence being temporal, w god as the beginning cause, is a central feature of the argument
scientific explanation applies with in the universe and therefore cannot apply to its actual creation
the cause of the universe must therefore have a personal explanation, i.e., intentionally created by an intelligent mind
this being must must have the power to create a universe from nothing (ex nihilo)
it must be outside time and space since it created time and space
as a timeless, external being, god didnt begin to exist so its then no contradiction in claiming god doesn’t have a cause
these are qualities that god would have, so the cause of the universe is god