From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=0.2 required=5.0 tests=BAYES_00,INVALID_MSGID, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fac41,2c6139ce13be9980 X-Google-Attributes: gidfac41,public X-Google-Thread: 1108a1,2c6139ce13be9980 X-Google-Attributes: gid1108a1,public X-Google-Thread: 103376,3d3f20d31be1c33a X-Google-Attributes: gid103376,public X-Google-Thread: f43e6,2c6139ce13be9980 X-Google-Attributes: gidf43e6,public From: donh@syd.csa.com.au (Don Harrison) Subject: Re: Safety-critical development in Ada and Eiffel Date: 1997/07/29 Message-ID: #1/1 X-Deja-AN: 260086320 Sender: news@syd.csa.com.au X-Nntp-Posting-Host: dev50 References: <33D7F7CD.3E36@flash.net> Organization: CSC Australia, Sydney Reply-To: donh@syd.csa.com.au Newsgroups: comp.object,comp.software-eng,comp.lang.ada,comp.lang.eiffel Date: 1997-07-29T00:00:00+00:00 List-Id: Ken Garlington wrote: :I responded elsewhere in this thread about difficulties in trying :to accurately measure thread timings at the object level, As I've already explained, SCOOP *does* support thread-level timing. The fact this has not yet been tested in a realtime system doesn't invalidate any logical arguments made about it. Empirical evidence doesn't *prove* anything. It merely adds credibility to theoretical arguments. We believe that General Relativity is valid because empirical evidence backs it up. But arguments made about its effects (gravitational lenses, behaviour of clocks etc.) were valid even *before* they were observed empirically. Observing these phenomena merely helps us to *believe* that it's a valid model of reality. A good example of how empirical observation proves nothing is found in the breakdown of Classical Physics. It was thought to be a valid physical model because empirical observations backed it up. The fact that those observations didn't *prove* its validity can be seen by its failure to explain *other* subsequent empirical observations - namely those concerning objects with high relative velocities. These observations conflicted with the theoretical model and led to Einstein's formulation of Special Relativity. Even though Special Relativity has been observed to be a better physical model, it can never be *proven* by those observations. Don. =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Don Harrison donh@syd.csa.com.au