From wetblu!uunet!fanny!I2Wash.Com!I2B_DB Sat Jun 2 22:45:16 1990 Return-Path: Received: by marob.masa.com (/\=-/\ Smail3.1.18.1 #18.7) id ; Sat, 2 Jun 90 22:45 EDT Received: by wetblu.hollander.com (/\=-/\ Smail3.1.16.1 #16.12) id ; Sat, 2 Jun 90 21:40 EDT Received: from cbmvax.UUCP by uunet.uu.net (5.61/1.14) with UUCP id AA11418; Sat, 2 Jun 90 11:59:45 -0400 Received: by cbmvax.cbm.commodore.com (5.57/UUCP-Project/Commodore Jan 13 1990) id AA11034; Sat, 2 Jun 90 03:04:58 EDT Received: by snark.uu.net (smail2.3) id AA21113; 2 Jun 90 02:37:46 EDT (Sat) Received: from fanny.UUCP by uunet.uu.net (5.61/1.14) with UUCP id AA12520; Fri, 1 Jun 90 10:25:33 -0400 Received: from I2Wash.Com (eve) by fanny.I2Wash.COM (4.0/SMI-4.0) id AA27664; Fri, 1 Jun 90 10:17:21 EDT Message-Id: <9006011417.AA27664@fanny.I2Wash.COM> Date: Fri, 1 Jun 90 10:25 EST From: wetblu!uunet!I2Wash.Com!I2B_DB Subject: Retaining Logical Connectives To: snark.uu.NET!lojban-list X-Vms-To: IN%"lojban-list@snark.uu.NET" Status: RO Jim C writes: >Just a brief note. Old Loglan was intended to be a "logical language", >and hence logical connectives were a major design feature, so that >essentially you could "speak symbolic logic", believed in those days to >be helpful for the thought processes. Lojban is intended to carry on >the Loglan tradition. As a result there has come to be a plethora of >logical connective grammar forms for just about every substructure in >the grammar. > >In -gua!spi the logical connectives were one of the first features to >go. In my Loglan writing I found that I used them surprisingly rarely. >I won't give examples, but -gua!spi emphasizes constructions like >these, chosen because these are what I found I used often, all of which >are handled via gismu and their arguments, not special grammar: > >1. A set or list with explicitly stated members. (Coffee, tea or milk: > choose one from the set.) (An old Loglan puzzle; try translating > that in Lojban.) >2. The union or intersection of sets -- the result may be left as a set > or may be extended. >3. A logical sentence connective (also causal, also any other gismu with > two event arguments). >4. An anaphor for a previous sentence, with replacement arguments. > (Example: Karen wants to go swimming. Me too. Meaning: I (speaker) > want to go swimming; "I" replaces "Karen".) Sorry to repeat all that, but I want to deal briefly with it. For my own purposes (and I realize that they may be unique), I would greatly regret removing the entire range of logical connectives from lojban. To me, as a computing scientist with a radical formal bent, lojban is one part of a continuum. I am working toward more precision in the specification of systems and in the construction of implementation of those systems. A lojban description is (to me) an extremely useful part in this process. A designer can refine and add rigor to his description without leaving the spoken language by re-phrasing things using more logical connectives in a more formal manner. Eventually, this description can be translated verbatim into predicate calculus notations suitable for formal specification and proof of programs and systems designs. For this reason, I have become wary of using too much set notation and set concepts in the specification process. While I recognize, and completely accept Jim's assertion that these are much more useful in normal speech and expression (given the examples above), for my purposes they may be overspecific. In particular, recent research (Dijkstra and Scholten, _Predicate_Calculus_and_Program_Semantics) suggests that set notations (as opposed to formulae in predicate calculus, which requires the full set of connectives) are more difficult to manipulate. So here is one vote for retaining the full set of connectives. I truly regret that my present knowledge of lojban does not allow me to enter this discussion more fully; I have strongly held prejudices concerning the use of logical connectives, particularly with regard to the importance of the equivalence and avoiding overspecific grouping of terms connected by associative operators (like the equivalence). Soon, I hope. Just one person's two cents worth...... Dave Barton barton@i2wash.com