The LOOPS primer, published in 1987, captured well the essence of exploratory programming in Lisp:

The LOOPS interface provides both a programming tool and a thinking tool. As you develop a new system, each preliminary version provides an object for thought and discussion. The preliminary versions are a crucial part of the design process.

LOOPS (Lisp Object-Oriented Programming System) is the OOP extension of Interlisp.

http://www.bitsavers.org/pdf/xerox/interlisp-d/198510_Koto/3102242_Xerox_LOOPS_A_Friendly_Primer_Mar87.pdf#page=60

#interlisp #oop #lisp