The Principle of Indirection in Computer Science

"Any   problem   in   Computer Science   can be solved   with    another level   of   indirection."

As per    Wikiquote    this famous remark has been attributed to the renowned Computer Scientist    David Wheeler    in
   "Principles for Computer System Design."    Turing Award Lecture given on February 17, 1993    by    Butler Lampson.

Also see the blurb on    Indirection    in Wikipedia.

For actual examples of this principle being put to good use, please refer to   lecture viewgraphs on Design Principles  
from Prof. Yin Zhang's web-page in CS Dept., Univ of Texas, Austin.
(it is one of the first few links that came up in a Google search on the string "Computer Science Principle of Indirection")

Cannot resist a joke ...

Claim : Computer Science is not a real science

Proof : For at least 2 reasons