procedure of the model usually we just use it to learn and we learn a one-shot model but here gradient descent is part of the model so they introduce energy functions here and they say okay we can have a policy on X so if we're given a concept W and if we're given an A we can have a policy over X which basically means we can find X's that are compatible with that by running gradient descent here you see there is an XK minus 1 and we are running gradient descent on the energy function with respect to X to find a better X