In this talk, I will share some exciting inventions under development by our research group, using light intensity measurements to transduce mechanical deformation of an artificial skin to replicate the human sense of touch. As background, I will briefly summarise what we know about human touch, and the ongoing 50+ year struggle to replicate this sense. I will highlight the hardware and data challenges we must overcome if we are to endow robotic systems with a human sense of touch. I will share some of our own recent innovations, of which we are proud. And finally, I will argue the essential role that touch will play in the ongoing robotics revolution, by enabling robots to learn about the physical world through tactile exploration – how could a machine master the physical world by only looking and never touching?