Hilbert’s Foundations of Geometry in 1899 made Poincaré think of “reasoning machines” before Hilbert did. Poincaré found the idea “deadly for teaching, and desiccating for researchers” but indispensable for telling when intuitions have been fully expressed. A machine will use stated axioms without the vague intuitions Poincaré considered vital to learning and research. Years of famously intuitive creativity, plus boundless faith in technology, as well as the impact of Hilbert, led Poincaré to see that machines could aid human intuition but not replace it, precisely because machines have no intuition. This relates to recent machine achievements in Lean and HoTT, and to the issues in Akshay Venkatesh’s essay.