The ongoing revolution in the scientific understanding of memory, mind and brain began in 1953 with amnesic patient Henry Molaison, known widely only as HM until recently. To remedy life-threatening epilepsy at age 27, Henry underwent surgery that inadvertently destroyed brain structures in the medial temporal lobe, and he suffered catastrophic memory failures for the remaining 56 years of his life. Case HM was a major earthquake that forever reshaped the intellectual landscape of memory, mind and brain. Case HM also helped the world understand what memories are and why the distinction between new versus old memories is so important. The ungrammatical sentences violated rules governing many different types of conceptual relations, including time relations, number relations, reflexive gender relations and simple reflexive relations. Methodological flaws that favoured null results compounded the impression that HM was a “pure memory case.”.