This is a widespread misconception. The first Smalltalk version in 1972 didn't even have inheritance. Although Kay is ascribed the term object orientation, he understands it to mean something quite different than most. It was Ingalls who first introduced the properties generally referred to as object-oriented and implemented in Simula as early as 1967 into his version Smalltalk-76. The influence of Smalltalk is generally overestimated.