The natural philosopher Michael Faraday and the psychologist Jean Piaget experimented directly with natural phenomena and children. While Faraday originated evidence for spatial fields mediating force interactions, Piaget studied children's cognitive development. This paper treats their experimental processes in parallel, taking as examples Faraday's 1831 investigations of water patterns produced under vibration and Piaget's interactions with his infants as they sought something he hid. I redid parts of Faraday's vibrating fluid activities and Piaget's hiding games. Like theirs, my experiences showed that incomplete observations and confusions accompanied—and facilitated—experimental developments. While working with things in their hands, these experimenters' minds were also engaged, inferring new, more coherent understandings of the behaviors under study. Transitory ripples disclosed distinct patterns; infants devised more productive search methods. From the ripples, Faraday discerned an oscillatory condition that informed his subsequent speculations about light. From the infant search, Piaget identified experimenting as a child's means of developing self and world, later envisioning its infusion into education. Taken together, these two stories demonstrate that cognitive capacities emerge in the actual process of experimenting. This finding eclipses the historical context in its implications for education today. When learners pursue their own experiments, their minds develop.