David Wheeler (Attributed in: Butler Lampson. Principles for Computer System Design. Turing Award Lecture. February 17, 1993.) Wheeler is said to have added the appendage "Except for the problem of too many layers of indirection." Also "All problems in computer science can be solved by another level of indirection". (Diomidis Spinellis. "Chapter 17. Another Level of Indirection". Beautiful Code: Leading Programmers Explain How They Think. O'Reilly Media. June 2007.) "Indirection" is often changed to "abstraction". The quote is called the fundamental theorem of software engineering by Andrew Koenig.