This proverb suggests that a person’s core character, habits, or nature cannot be changed, no matter the circumstances. It implies that fundamental traits are fixed, often used to express skepticism about someone’s ability to reform or to justify distrust based on past behavior. The phrase carries a fatalistic or cautionary tone.

The phrase comes from the Bible, Jeremiah 13:23 (King James Version, 1611): ‘Can the Ethiopian change his skin, or the leopard his spots?’ The verse questions the possibility of altering innate qualities. By the 16th century, it was a common English proverb, appearing in John Lyly’s *Euphues* (1578). Its use in literature, including by Shakespeare and later Dickens, reinforced its place in English to describe unchangeable character, often with moral undertones.