Before discussing several "category mistakes" in computer science in follow-up posts, it is much preferred to first introduce a few categorical distinctions and definitions and to subsequently test these concepts on the writings of computer science's greatests (i.e., the writings of the people I and many others admire the most).
In 2006 I defended my Ph.D. thesis at KU Leuven. Dr. X from abroad was in my defense committee. He had taken the liberty a few days earlier to share with me some of the "fundamental limitations" he had found with regard to transformational systems, such as the system I had designed, implemented, and documented for my Ph.D. defense. (A comprehensive overview of my system later appeared in Science of Computer Programming ). Dr. X had already published his theoretical insights and he wanted me to incorporate his findings into my Ph.D. dissertation.