To what other contemporary practices was zazen supposed to be the superior alternative?What are its practical details,and in what way does it aid the practitioner in the attainment of realization?

What is zazen?

REVISION

Based on our readings in Dōgen’s Shōbōgenzō, what is zazen?

You may want to address the following questions in your discussion: to what other contemporary practices was zazen supposed to be the superior alternative?What are its practical details,and in what way does it aid the practitioner in the attainment of realization? What, for Dōgen, secures its utmost spiritual efficacy? (only use the two sources attached)