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In a message dated 6/4/2002 8:42:18 PM Central Daylight Time, a-rosta@hidden.email writes:. Incredible I'm not sure why this is incredible. Loglan/Lojban is a logical language exactly in the sense that its syntax is based directly on first order predicate logic as usually expressed. And the crucial aspect of that, for JCB's original purpose, was that it had only two categorematic types, as against the SAE's typical half dozen or so. To be sure, one could argue that the languages that have derived from that original program now have rather more types, but, in fact, this can be viewed as a derivational component not much developed in logic, though present. Indeed, the derivate languages push into several peripheral areas of logic in the quest for the expressivity of natural languages. But, through all this, logical structure in &'s sense was not a consideration, for logicality was not a goal. On the other hand, given the base in the language of formal logic, logical structure could be assumed to parallel syntactic structure since the logical structure was assumed just to be that of formal logic, i.e., of the syntactic struture of the derivate language. All of the assumptions this last embodies are somewhat off, of course. Logical structure is not quite exactly first order logic in standard form. The syntactic structures of Lo*an are not quite exactly that of first order logic (but off in different ways from logical structure). And, of course, the actual shape of logical structure is not yet known completely, though enough differences are known to assure the claim above. Thus Lo*an are pretty clearly the standard for syntactic-logical interface, though not yet perfect even in the areas of logical structure that are finished. It is about ninety-five percent right and it is a fully functioning language. Nothing else can now match either of those and certainly not their combination. But... Mike: <(1) While the formal syntax of the particular example you give indeed does not formally parallel the logical structure it is deemed to represent, nevertheless, the logical structure is clearly unambiguously established. Purely speculatively, could we not somehow re-analyze the syntax in order to reflect the logical structure? If so, would such a re-analysis satisfy your objection?> It should be noted that the claim that {ro nanmu cu prami lo ninmu} is actually in perfectly good first-order logical form, even a standard form, though in the semantic representation logical form (as far as we know, this is a not-completely-resolved issue among semantic theorists). <In the example you give, the closest we come to capturing the logical structure using plain English as opposed to logicians' jargon is: - If something is a man, then it loves at least one woman. Or a bit briefer: - If it's a man, it's a woman-lover.> Or "Every man loves some woman or other." The other two are, of course, going to get interpreted correctly, but are overtly wrong, one for the wrong quantifier and scope, the other for lacking overt quantifiers altogether. Even if you (or &) does not like the natural English or Lojban forms, the rules for going to some preferred form -- at least of the usual sorts (I am unclear what & has in mind as the final result) are clear and mechanical. To be sure they can give rise to a variety of different forms, but these are either provable equivalent or differ only in underlying assumptions, which then have to be spelled out. (BTW the conditional form would usually have to be deconditionalized for most natural-language cases. An arguable -- and often argued -- point) Quantifiers are not where the problem in Lo*an are, unless you include -- as & does -- indirect question markers (and maybe direct ones) and lambda variables in the list. Then the problem is just to mark scope -- or, more accurately, depth. The peripheral cases (no less important for that, of course) need to be examined and some rules or devices (Lo*an is big on subscripting -- yuck!) devised. The problem is not inherent, only due to a lack of attention. The other problem is anaphora, for which Lo*an has Lord knows how many devices, but countless insoluble cases, often because the devices require a kind of syntactical awareness that is hard to achieve even with the sentences written out in front of you, let alone on the fly in converation. Yet even with all these devices there remain real-life cases that are inaccessible: anaphora for a term reached by scaling one tree, swinging to another branch, and scurrying back down that branch, for example. The only devices to use in this case are fuzzy ones, not precise ones, and thus liable to screw up syntactosemantic rules, however well they work in practice. |