Return-Path: Delivery-Date: Received: from leopard.cs.byu.edu (no rfc931) by swan.cl.cam.ac.uk with SMTP (PP-6.5) outside ac.uk; Wed, 17 May 1995 14:09:25 +0100 Received: by leopard.cs.byu.edu (1.37.109.15/16.2) id AA256892932; Wed, 17 May 1995 06:15:32 -0600 Sender: info-hol-request@lal.cs.byu.edu Errors-To: info-hol-request@lal.cs.byu.edu Precedence: list Received: from relay.cs.ruu.nl (infix.cs.ruu.nl) by leopard.cs.byu.edu with SMTP (1.37.109.15/16.2) id AA256862921; Wed, 17 May 1995 06:15:21 -0600 Received: from [131.211.81.185] (McSwierstra.cs.ruu.nl) by relay.cs.ruu.nl with SMTP id AA23057 (5.67a/IDA-1.5 for ); Wed, 17 May 1995 14:13:09 +0200 X-Sender: doaitse@relay.cs.ruu.nl Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 17 May 1995 14:18:07 +0100 To: Lawrence C Paulson , homeier@cs.ucla.edu (peter v. homeier) From: doaitse@cs.ruu.nl (S. Doaitse Swierstra) Subject: Re: Question on Dijkstra Quote Cc: info-hol@leopard.cs.byu.edu At 10:33 17-05-1995, Lawrence C Paulson wrote: >It is on page 6 of > >@InCollection{dijkstra-notes, > author = "Edsger W. Dijkstra", > title = "Notes on Structured Programming", > booktitle = "Structured Programming", > publisher = "Academic Press", > year = 1972, > editor = "O.-J. Dahl and E. W. Dijkstra and C. A. R. Hoare"} > >The precise quote is > >"Program testing can be used to show the presence of bugs, but never to show >their absence!" > >I recall that Dijkstra later objected that referring to errors as "bugs" >diminishes their significance... > > Larry Paulson And in "A Discipline of Programming", Prentice-Hall 1976, it says on page xvi: "None of the programs in this monograph, needelss to say, has been tested on a machine" Doaitse Swierstra __________________________________________________________________________ S. Doaitse Swierstra, Department of Computer Science, Utrecht University P.O.Box 80.089, 3508 UTRECHT, the Netherlands WWW: http://www.cs.ruu.nl/ tel: +31 30533962, fax: +31 30513791 email: swierstra@cs.ruu.nl __________________________________________________________________________