Felix is a second year PhD student in the cognitive science department working on cognitive tools for planning and physical reasoning. Humans use cognitive tools: tools that help think. How do such cognitive tools support humans in making efficient use of their limited cognitive capacities on hard computational problems such as planning? Felix researches the computational nature of such tools using agent-based simulations. This research—best described as computational cognitive science—aims to shed light on how humans achieve so much from so limited cognitive resources.