Prominent best-selling author and critically acclaimed motivational speaker Dr. Wayne Dyer has died at 75, his family and publisher confirmed on Sunday, according to NBC News. 

Reid Tracy, chief executive of Hay House, Dyer's publisher, said the author died Saturday night in Maui, Hawaii. The cause of the death has not been released, reports The Washington Post.

Dyer's debut work, "Your Erroneous Zones: Step-by-Step Advice for Escaping the Trap of Negative Thinking and Taking Control of Your Life," published in 1976, became a nationwide best-seller, selling about 35 million copies. The book rose to the country's best-seller lists, where it remained for more than a year.

The author wrote about 40 more books during his writing career. He also became a media sensation, going around the country on tours and becoming close friends with prominent celebrities, among them Oprah Winfrey and Ellen DeGeneres. 

Millions of readers have credited Dyer's teachings, which employ an eclectic mix of spiritual philosophies, in helping them relinquish a guilt-focused lifestyle. His teachings have also helped in encouraging people to adopt a clear, focused lifestyle that will enable anyone to reach success, according to Yahoo! News.

Dyer was diagnosed with chronic lymphocytic leukemia in 2009, though he said that it was being treated by a mixture of positive thinking, daily exercise and psychic surgery, which was being remotely performed by João Teixeira de Faria, a notable Brazilian medium.

Dyer's death is the latest among personalities who have affected countless lives during their lifetime. Just recently, Augusta Chiwy, "The Forgotten Angel of Bastogne," who was credited for saving countless lives in the Second World War, also passed away, as covered in this HNGN article.