The book's central premise is that in today's complex and fast-paced world, it is no longer enough to simply be effective. Instead, individuals and organizations must strive to find their unique voice and purpose and use it to make a meaningful difference in the world. Covey argues that the 8th habit is the key to achieving this, and that it involves discovering one's own personal "voice" and using it to inspire and lead others. Overall, "The 8th Habit" is a thought-provoking book that encourages readers to think deeply about their own values, goals, and aspirations, and to take action to make a positive impact on the world around them.