The Principle of Sufficient Reason (PSR) in its classic form issimply that nothing is without a reason (nihil est sineratione) or there is no effect without a cause. AsLeibniz remarks, this principle “must be considered one of thegreatest and most fruitful of all human knowledge, for upon it is builta great part of metaphysics, physics, and moral science.” (G VII301/L 227) In the Principles of Nature and Grace, Leibnizsuggests that the claim that nothing takes place without a sufficientreason means that nothing happens in such a way that it is impossiblefor someone with enough information to give a reason why it is so andnot otherwise. In the Monadology and elsewhere, however,Leibniz frankly admits that “most of the time these reasonscannot be known to us.” (G VI 612/AG 217) While the idea thatevery event must have a cause and that there is a reason why everythingis so and not otherwise again might not seem novel, it is theconnection that Leibniz sees between this principle and his othermetaphysical principles that is noteworthy. According to Leibniz, PSRmust actually follow from PIN, for if there were a truth that had noreason, then there would be a proposition whose subject did not containthe predicate, which is a violation of Leibniz's conception oftruth.


Satisfied customers are saying