Mark Grannis is a husband, father, teacher, and lawyer in suburban Maryland. In 2019, after 30 years of practicing law in Los Angeles and Washington, D.C., he began teaching at The Heights School in Potomac, Maryland, where he teaches logic and history. He is the author of The Reasonable Person: Traditional Logic for Modern Life (2023) and its Teacher Supplement (2024). He is also the author of Should You Go to Law School? Knowing How to Know (2026), and he shares daily quotations from his classroom on his Substack, Tips While Shaving.