This episode focuses on how we humans "construct" our perceptions of reality using our "Bayesian Brain" to integrate incoming sensory information with our preconceived notions of the world around us. Citing work done by Dr. Anil Seth, Professor of Cognitive and Computational Neuroscience at the University of Sussex in England, Bob and Julia discuss this and related topics appearing in the special edition of "Scientific American", titled: "Truth Lies & Uncertainty."