 Bergson himself says that his final book, The Two Sources of Morality and Religion, develops ideas from Creative Evolution. It attempts to show that there are two sources from which two kinds of morality and religion evolve. As always with Bergson, Kant is at issue, in this case his moral philosophy. And as usual, Bergson starts by differentiating within a mixture. Under the word “morality” or under the phrase “moral obligation,” there is a mixture of two kinds of morality.