Often in discussions on pranayama, we talk about the techniques and the benefits or effects. In this talk by Yoganand Michael Carroll, we will focus on the philosophy behind the practice. Throughout the history of yoga and pranayama, the techniques were developed and practiced for the realization of a philosophy. The philosophy outlined a path and a goal, and the techniques, whether meditations, pranayamas or asanas, were designed to lead the student closer to that goal. When we look at pranayama from this perspective, we can understand more of why the techniques are the way they are. We see that there is a rational behind the pranayamas, even though what was a desirable effect under one philosophy might be undesirable under a philosophy that arose later. As we look at the history we see that the philosophy changed over the years. From finding the ‘unchanging self’ of Vedanta, to merging with the universe as a Tantric, we see an evolution. Practices from before were often re-purposed when the philosophy changed. In this talk we will explore from the beginning to modern times how goals of pranayama practice changed and as the goals changed the techniques or understanding of the techniques changed also.