The geometer who kept conic sections classy. Serenus of Antinoupolis (fl. 4th century CE) wrote elegant treatises on cylinders and cones, making sure the math behind the curves stayed sharp and stylish. He wasn’t trying to revolutionize geometry — just to explain and preserve it with crystal clarity. His works helped bridge the gap between Apollonius and later thinkers, showing that even in late antiquity, math still had grace, rigor, and serious curve appeal.