Leonard Peikoff · CC BY-SA 3.0

A philosopher who spent decades as Ayn Rand's closest intellectual associate, and whom she named heir to her estate and ideas. After teaching philosophy and hosting a nationally syndicated radio program, Peikoff co-founded the Ayn Rand Institute in 1985 to carry Objectivism forward as an organized school of thought, and wrote several books systematizing Rand's philosophy for readers who came to it after her death.