Complex sentence: As a young man he repudiated these claims, and declaring himself unbound by any tradition or philosophy, spent the rest of his life presenting a unique philosophy of life around the world in talks, discussions, and writings.
Split into simpler sentences: As a young man he repudiated these claims and declared himself unbound by any tradition or philosophy. He spent the rest of his life presenting a uniquely expressed philosophy of life around the world in talks, discussions, and writings.