Ivan Sutherland’s seminal Sketchpad application was an early inspiration for OOP. It was created between 1961 and 1962 and published in his Sketchpad Thesis in 1963. The objects were data structures representing graphical images displayed on an oscilloscope screen, and featured inheritance via dynamic delegates, which Ivan Sutherland called “masters” in his thesis. Any object could become a “master”, and additional instances of the objects were called “occurrences”.

'Wenn es Ökonomen gelingen könnte, dass sie als bescheidene, kompetente Leute gelten, auf einer Ebene mit Zahnärzten, das wäre herrlich' Keynes, Maynard, 1930