In Surprised by Joy, C.S. Lewis recalls that his childhood dog was named Jacksie. The dog’s death was a major emotional event for Lewis and contributed to the adoption of the name Jacksie as his own preferred nickname during childhood.
Lewis’s brother Warren had given the dog the name Jacksie after a boy named Jack, who had been killed in a road accident. When Lewis was about four years old, he announced that he would also be called Jacksie. The name was later shortened to Jack, which became the familiar name used by friends and colleagues throughout his life.
Surprised by Joy, published in 1955, is not a complete conventional autobiography. It focuses especially on Lewis’s intellectual and spiritual development, including his childhood reading, his move away from Christianity, and his eventual return to religious belief.
The childhood nickname helps explain why many biographies refer to him as Jack Lewis rather than Clive Lewis. Jacksie is also sometimes misremembered as the name of Lewis himself from birth, but the name originally belonged to his dog before becoming his personal nickname.