"Linux is useless without a shell like GNU. But that doesn't mean those artifacts are somehow abstractions."
There's abstract as "existing in thought or as an idea but not having a physical or concrete existence". A computer program not really physical. It can be represented as physical state as in neural tissue. DRAM charge conditions or magnetic fields on a hard disk. There's abstract as "consider (something) theoretically or separately from something else". Linux is abstract in this sense as it enables users not to think about certain issues. There's abstract as "extract or remove (something)" as one does when refactoring. To capture the essence or to generalize over alternative implementations. I make no distinction between mathematical abstractions and computer programs. Most people think of computer programs as operational and imperative, but the artifact of a Mathematica code and a derivation in front of a whiteboard can be the same referent. Marcus ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College to unsubscribe http://redfish.com/mailman/listinfo/friam_redfish.com FRIAM-COMIC http://friam-comic.blogspot.com/ by Dr. Strangelove
