When did people favor composition over inheritance?

Explores the historical origins and context of the "favor composition over inheritance" principle from the Gang of Four's Design Patterns book. Examines the three-page discussion that led to this aphorism, including the white-box versus black-box reuse distinction, language-specific considerations in Smalltalk and Java, and the compile-time versus runtime trade-offs. References Barbara Liskov's earlier work on subtypes and polymorphism, highlighting that composition and inheritance aren't the only options—first-class procedures offer a third alternative that the simplified aphorism overlooks.