Not long ago I was reading William Rowe’s treatment of the cosmological argument in his Philosophy of Religion: An Introduction (4th ed.). According to Rowe, the cosmological argument depends on the principle of sufficient reason (PSR). Rowe might be right but we have to bear in mind that not everyone understands PSR in the same way.
In this post I only wish to comment on the strange manner in which Rowe formulates PSR. According to Rowe, PSR has two parts:
We may state PSR, therefore, as the principle that there must be an explanation (a) of the existence of any being and (b) of any positive fact whatever (p. 23).
I think that Rowe’s PSRb is superfluous. It is already implied by PSRa. Here is an example that Rowe gives to justify the two distinct parts of his formulation of PSR:
Thus, if we come upon a man in a room PSR implies that there must be an explanation of the fact that that particular man exists. A moment’s reflection, however, reveals that there are many facts about the man other than the mere fact that he exists. There is the fact that the man in question is in the room he’s in rather than somewhere else, the fact that he is in good health, and the fact that he is thinking of Paris rather than, say, London. Now the purpose of the second part of PSR is to require an explanation for these facts as well (p. 23).
So, in Rowe’s view, PSRa is only relevant to the fact that the man exists. PSRb needs to be stated to take care of all the other facts.
But, I would say, all those facts are already taken care of by PSRa. Are they not all about existence in some way? Can we not ask:
1. Why does the man exist in this room rather than another?
2. Why does good health exist in him?
3. Why does the thought of Paris exist in his mind and not that of London?
Or, if you like, you could say that, since Rowe considers the existence of something a fact (“…PSR implies that there must be an explanation of the fact that that particular man exists.”), PSRa is superfluous. Either way, Rowe’s formulation of PSR seems to be redundant.