Essence of Reflection brings not only the author's martial arts experiences to the forefront, but also his life experiences in order to highlight some reflective thoughts we all can consider along our own respective journeys. A martial arts book from 40 years ago serves as the inspiration for Dan to provide commentary and discussion on an array of topics that can prove beneficial for everyone.

Dan Popp began his study of Isshin Ryu Karate in 1982 under his father, Frank Popp. He eventually joined the Order of Isshin-Ryu family in 1996 and is currently ranked roku-dan. Dan is also ranked go-dan in Manasyu Karate, yon-dan in Kendo, and Lakan Isa (1st degree black belt) in Kombatan. Dan was named the 2008 Male Instructor of the Year by the Isshin-Ryu Hall of Fame. In 2013 he was inducted as the 101st member of the Isshin-Ryu Hall of Fame.

Dan learned the traditional Japanese art of Shodo under his Kendo sensei, the late Duk Yeong Kim, and continues to practice this art to honor Kim sensei. He has exhibited his art in both Harrisburg, PA and Lancaster, PA. He has previously authored two books about his former Kendo/Shodo instructor: The Floating Brush as well as Sensei's Final Lessons.