Creating mathematical diagrams is essential for both developing one’s intuition and conveying it to others. However, formalizing diagrams in most general-purpose tools requires painstaking low-level manipulation of shapes and positions. We report on early work on PENROSE, a system we are building to automatically visualize mathematics from notation. PENROSE comprises two languages: Substance, a domain-specific language that mimics the declarativeness of mathematical notation, and Style, a styling language that concisely specifies the visual semantics of the notation. Our system can automatically visualize set theory expressions with user-defined styles, and it can visualize abstract definitions of functions by producing concrete examples. We plan to extend the system to more domains of mathematics.