From owner-cse584-sp07-list@LISTSERV.BUFFALO.EDU Sun Apr 1 16:40:42 2007 Received: from ares.cse.buffalo.edu (ares.cse.Buffalo.EDU [128.205.32.79]) by castor.cse.Buffalo.EDU (8.13.6/8.12.10) with ESMTP id l31KegUs004403 for ; Sun, 1 Apr 2007 16:40:42 -0400 (EDT) Received: from front1.acsu.buffalo.edu (upfront.acsu.buffalo.edu [128.205.4.140]) by ares.cse.buffalo.edu (8.13.6/8.13.6) with SMTP id l31KecTl079004 for ; Sun, 1 Apr 2007 16:40:38 -0400 (EDT) Received: (qmail 7904 invoked from network); 1 Apr 2007 20:40:38 -0000 Received: from mailscan7.acsu.buffalo.edu (128.205.6.158) by front1.acsu.buffalo.edu with SMTP; 1 Apr 2007 20:40:38 -0000 Received: (qmail 7903 invoked from network); 1 Apr 2007 20:40:36 -0000 Received: from defer.acsu.buffalo.edu (128.205.7.58) by front3.acsu.buffalo.edu with SMTP; 1 Apr 2007 20:40:36 -0000 Received: (qmail 9754 invoked from network); 1 Apr 2007 20:40:27 -0000 Received: from listserv.buffalo.edu (128.205.7.35) by defer.acsu.buffalo.edu with SMTP; 1 Apr 2007 20:40:27 -0000 Received: by LISTSERV.BUFFALO.EDU (LISTSERV-TCP/IP release 14.5) with spool id 4279514 for CSE584-SP07-LIST@LISTSERV.BUFFALO.EDU; Sun, 1 Apr 2007 16:40:26 -0400 Delivered-To: CSE584-SP07-LIST@LISTSERV.BUFFALO.EDU Received: (qmail 21288 invoked from network); 1 Apr 2007 20:40:26 -0000 Received: from mailscan6.acsu.buffalo.edu (128.205.7.95) by listserv.buffalo.edu with SMTP; 1 Apr 2007 20:40:26 -0000 Received: (qmail 10998 invoked from network); 1 Apr 2007 20:40:26 -0000 Received: from hadar.cse.buffalo.edu (128.205.32.1) by smtp4.acsu.buffalo.edu with SMTP; 1 Apr 2007 20:40:26 -0000 Received: from hadar.cse.Buffalo.EDU (ag33@localhost [127.0.0.1]) by hadar.cse.Buffalo.EDU (8.13.6/8.12.10) with ESMTP id l31KePKl020402 for ; Sun, 1 Apr 2007 16:40:25 -0400 (EDT) Received: (from ag33@localhost) by hadar.cse.Buffalo.EDU (8.13.6/8.12.9/Submit) id l31KeP0t020401; Sun, 1 Apr 2007 16:40:25 -0400 (EDT) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-UB-Relay: (hadar.cse.buffalo.edu) X-PM-EL-Spam-Prob: : 7% Message-ID: Date: Sun, 1 Apr 2007 16:40:25 -0400 Reply-To: Albert Goldfain Sender: "Philosophy of Computer Science, Spring 2007" From: Albert Goldfain Subject: The most important post in Phil of CS history!!! To: CSE584-SP07-LIST@LISTSERV.BUFFALO.EDU Precedence: list List-Help: , List-Unsubscribe: List-Subscribe: List-Owner: List-Archive: X-UB-Relay: (hadar.cse.buffalo.edu) X-DCC-Buffalo.EDU-Metrics: castor.cse.Buffalo.EDU 1335; Body=0 Fuz1=0 Fuz2=0 X-Spam-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,PLING_PLING autolearn=no version=3.1.7 X-Spam-Checker-Version: SpamAssassin 3.1.7 (2006-10-05) on ares.cse.buffalo.edu X-Virus-Scanned: ClamAV 0.88.6/2989/Sun Apr 1 15:31:48 2007 on ares.cse.buffalo.edu X-Virus-Status: Clean Status: R Content-Length: 1909 Okay...now that I have your attention :-) About half of the position papers I graded this week (pp3) had terminology problems with the terms "valid" "invalid" "true" and "false"...despite the reminder atop the grading rubric. Here it is again: -------------------------------------------------------------------------- One terminological reminder: sentences can be true or false (or you can agree or disagree with them) arguments (which are sequences of sentences) can be valid or invalid (they can be sound or unsound, too) conclusions of arguments can *follow validly* or *not follow validly* from the premises of the argument Therefore: sentences cannot be valid or invalid, or sound or unsound arguments cannot be true or false ------------------------------------------------------------------------ Now a common mistake was to say "conclusion (5 or 6) is invalid" which i took too mean "conclusion (5 or 6) does not follow (from the preceding premises)". And people who did something like this *and* said whether they believed/disbelieved the conclusion got credit despite the terminological problems (but please pay attention to this on the next paper). However, if you *only* wrote something on your paper like "conclusion 5 is valid (or invalid)" and did not state whether or not you believed conclusion 5 then you *must* have missed one of the components of what you had to do. If you meant "true" by valid or "false" by invalid then you stated your belief but did not assess validity. If you meant the "argument ending at conclusion 5 is valid" or "the argument ending at conclusion 5 is invalid" then you assessed validity but did not state your belief/disbelief in the conclusion. SO THIS IS NOT A MINOR TERMINOLOGY POINT I AM MAKING...and it can make the discussion around your conclusion seem very confused...so please check for this in PP4 and PP5. Thanks, Albert