Since the dawn of mankind, a few existential questions have persisted through the ages. How did the universe begin? What is the meaning of life? How in the world can we make an echo using only gradients? Well the good news is we’re going to answer this last question and free up your mind to find the answers to the other ones. Please tell me when you figure it out. And in the process we’re going to encounter a disturbing and closely held secret regarding gradient fields. But what if I told you this secret was actually the key to our salvation in understanding advanced MRI physics? So tell your family and friends you love them, give the dog one last pet and prepare yourself as by the end of this lecture, life will never be the same. This is the Gradient Recalled Echo… EXPLAINED.