Snyder's prolific and pioneering contributions to Optical Physics, especially Fibre Optics, have guided and oriented research in a field of great technological importance. Simultaneously, his many seminal contributions to the physics of visual photoreceptors of vertebrates and insects have provided directions and challenges for visual physiologists. Whether bridging physics, biology and mathematics, or in optical physics, a characteristic theme of his work has been a remarkable capacity to reduce exceedingly complex phenomena to an intuitive, tractable form.