'THE CRITIQUE OF PRACTICAL REASON' by Immanuel Kant. Humans, the author mentions, are quite free with the theoretical use of reason and are stranded with unattainable notions. That brings the need to have a vision about the practical use of reason, where, the influence of reason on free will and its actual manifestation can be subjected to scrutiny. Unlike pure reason, where we start with our senses and formulate principles to meet the end, in practical reason, we start with the governing principles, apply our senses, and arrive at the imperatives.
The book then discusses two theorems and analyzes the motive of practical reason. Theorem One: one cannot make a practical principle based on one's desire. Two: All practical principles branch out of one's ideas of self-love, or private happiness. While examining the scope of such principles as a part of the moral standards of the society, how one arrives at prudent choices, is elaborated. A discussion the doctrine of happiness versus the doctrine of morality as the underlying theme of every society, follows here. Quite interestingly, the nuances of practical reason in accommodating well, both the views.
Another equally thrilling investigation comes next. Nature of God is examined in the context of creation of things in this world, in the light of practical reason. Things are seen here, both as noumena ( present for ever) and as just experiences or appearances.
Part II of the book looks at another two the aspects of practical reason. How, rational conduct could necessitate a via-media between pure reason and actual endeavors. And how, over the years such adjustments took the shape of philosophy or science. And, since all this follow according to the local flavors of thought, we happen to possess many different schools of philosophy, about such things like virtue, or happiness, or common good.
I enjoyed this book. Though I took some time to grasp the content, the language being a little hard for me, it made a lot of things clear. As the book says, if we let philosophy act as a guardian of science, the resulting doctrines of all such examinations shall appear in a clear light.