ARGUMENTS FOR MONOTHEISM 183Principles of Sufficient Reason
1 The Everlasting World Strategy requires something like this: (PSR1) If it
is logically possible that something depends for its existence on
something else, then it does depend for its existence on something else or
What can depend for its existence on something else does depend for its
existence on something else.
2 The World Has A Beginning Strategy requires something like this:
(PSR2) What begins to exist must have a cause of existence or Nothing
can simply begin to exist without being caused to do so.
3 The Inclusive Strategy requires something like this: (PSR1) and (PSR 2 ).
Crucial premises
The different strategies will also require somewhat different premises along
these lines.
1 The Everlasting World Strategy requires some such premise as this: It is
logically impossible that everything that exists exists dependency.
2 The World Has A Beginning Strategy requires some such premise as this:
It is logically impossible that everything that exists has had a beginning
of existence.
3 The Inclusive Strategy requires something like this: (a) It is logically
impossible that everything that exists exists dependency and (b) it is
logically impossible that everything that exists has had a beginning of
existence.
The idea is that if the world is beginningless past, it does not exist
independently (because of the truth of (a)) and if the world has a beginning it
does not exist independently (because of the truth of (b)).
The inclusive strategy is safer with respect to one of its basic premises
which is a weaker claim than its analogues – one who uses it need not care
whether the world ever began to exist or not. But it is riskier with respect to its
version of the Principle of Sufficient Reason (it requires both PSR1 and PSR2).
Differences in conclusions
The strategies, of course, will also yield somewhat different conclusions.
Aristotle wants to infer from the world’s existence to God’s existence in a way
that does not require that God have made any choices or performed any