Alfred Paul "Al" Seckel (September 3, 1958 – 2015) was an American collector and popularizer of visual and other types of sensory illusions, who wrote books about them. Active in the Freethought movement as a skeptic in the 1980s, he was the co-founder and executive director of the Southern California Skeptics. News coverage arising from his connection to Jeffrey Epstein has stressed Seckel's misrepresentation of his education and credentials.