Why do you think Zen Buddhism has become so popular all over the world, But Advaita vedanta hasn’t? Originally, Zen is from Advaita vedanta. It has evolved from the Advaita philosophy. But Zen has become popular, but not Advaita. The reason is that Zen emphasizes on the truth of declaration. The decision is enough. The cognitive shift is enough! Unfortunately, we advaitis are somehow stuck with some form of practice, without making people understand the importance of cognitive shift. The cognitive shift itself will make you live the principles. It is unfortunate that we do not understand the importance of cognitive shift. We think that some form of practice is required. I do promote spiritual practices like kriyas, yoga and pranayama, for the purpose of purifying your bio-memory, purifying your body and to cure some diseases. But I tell you, that is not the first priority in spiritual
life. It may be like a pickle, but it is not the main meal! The main meal is cognitive shift! Shift in your cognition, shift in your perception, shift in your decision!'
(The Science of Living Enlightenment)