Thread: Principle of Sufficient Reason

Does the Principle of Sufficient Reason mean that all truths are necessary truths?

I'm not familiar with the Principle of Sufficient Reason, but I think it it fairly clear that all truths are not necessary truths. For instance, the fact that Christ is God's Son is a necessary truth. The fact that the statement "if a, then b" necessitates the statement "if not b, then not a" is a necessary truth. Now, something being a necessary truth doesn't have to mean it is self-justifying, for its necessary truth-value could be dependent upon another truth that is self-justifying. Make sense?

Now, the fact that not all truths are necessary can be seen by noting that it is a truth that I used the number of words I did for this post, or that George W. Bush became President as a result of last election. However, what makes those truths unnecessary is that they could have just as easily been falsehoods.

To put it simply the principle of sufficient reason is that which requires us to acknowledge that there is no fact or truth which lacks a sufficient reason why it should be so, and not otherwise. In other words, there is a sufficient reason for why a certain truth is the way it is rather than another. If you look at this principle, that Leibniz formulated, closely we will see that it seems to imply that all truths must be the way they are.

Indeed, because of God's eternal, providencial decree, there is a sense in which all truths are necessary. But I think that we do indeed need to speak of the truth value of statements in a way that relates it to our perspective. That can be seen as parallel to how we speak of time - for God is outside of time, but it is nonetheless a crucial concept for discussing truth from our side of the window.

In light of that, to speak of a "sufficient" reason for the truth of a statement does not seem to imply the necessary truth of that statement. For instance, the fact that I chose to use the words I did in typing this post is a "sufficient" reason for the truth of the statement that it has the number of words that it does. Nonetheless, from our side of the window, that statement could just have easily been false had I chosen to word things differently. So my choice of wording was a "sufficient" reason for that fact, but not a necessary reason.