American painter and graphic designer particularly known for his poster art and artistic ambigrams. Also a writer, he published a 1992 work called Wordplay that includes both ambigrams and essays.
He studied English at Dickinson College and later taught typography at Pennsylvania's Drexel University.
He was influenced by the work of M.C. Escher and inspired by the Taoist yin/yang symbol.
Born into a literary, academic, and artistic family, he was the son of a schoolteacher and the grandson of an artist and a poet.
He was the inspiration for the character of Robert Langdon in author Dan Brown's popular novel The Da Vinci Code.