The state of ethics is not good in our modern American society.
MacIntyre begins this treatise with an unpleasant hypothetical, that perhaps the current state of social discourse is that we are swimming in the disjointed jumble of different, competing ideas of justice and the meaning of the human life.
Are people mostly essentialist or existentialist today?
One of the key ideas in the book is the juxtaposition of Aristolte and Nietzsche, and variations on that theme. Aristotle's Nicomachean Ethics argues for ethics as the scientific process of determining what conduct will maximize the potential of the essential human nature. But ever since Nietzsche's rejection of essence, the culture also contains the antithetical view that life is essentially meaningless, and we impose meaning on it. Therefore, we're left in a world where the only reasonable way to discuss philosophy is indirectly through narrative.
The incompatibility of competing virtues.
There are many examples of these offered, but basically, MacIntyre discusses why certain ideologies are incompatible with others, because each ideology has its own set of ideas that govern it. Another aspect of this theme is that there is actually no common root in religious and philosophical modes, and the world is truly subject to different, alternative perspectives.
