As to Leibnitz, he is certainly a good philosopher, but in his Theodicée he goes too far and would have all actions necessary. His foreordained harmony is not the least credible nor feasible. If you can get a book entitled: [http://books.google.com/books?id=gI8PAAAAQAAJ An Essay on the Origin of Evil], by Dr W. King, you will find a much better solution of the question: 'whence comes evil?' Leibnitz does indeed reconcile it all with the goodness of God, but not so reasonably as Dr King.