In article <4806C111.6090400 / comcast.net>, Tom Cloyd <tomcloyd / comcast.net> wrote: >My thanks to the core contributors to this fascinating thread. It's >stretched me well past my boundaries on several points, but also >clarified some key learning I've picked from my own field (psychology & >psychotherapy). Here are a website with some papers that I found in my cursory research of the topic and might be interesting: http://www.praxis-his.com/sparkada/publications_journals.asp The Philosophical Transactions paper by Roderick Chapman reports that, using SPARK (a well-behaved subset of Ada), "Proof of the absence of run-time errors has been performed on programs of the order of 100 000 lines of code." Francis