null quantification: Difference between revisions

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(originally from [[tu'o]] and relevant to discussions of [[tu'o]] and [[lo'ei]] and similar creatures.)


''(originally from [[tu'o|tu'o]] and relevant to discussions of [[tu'o|tu'o]] and [[lo'ei|lo'ei]] and similar creatures.)''
I don't understand how the meaning of the bridi can be determined without quantifying over the underlying set, unless the set is one-membered. Perhaps the idea is simply that the quantifier is left unspecified so that it is glorked from context? That seems reasonable, but it's not equivalent to '''[[lo'ei]]''' (e.g. '''mi nitcu tu'o tanxe''' is not equivalent to '''mi nitcu lo'ei tanxe'''). --[[User:And Rosta|And Rosta]]
* If the set is one-membered, then you are still quantifying over that one member, though perhaps a bit trivially. I think that the idea (as [[User:xorxes|xorxes]] has expounded) is that the quantifier is deleted, resulting in the intensional meaning of the selbri being added to the main bridi without extensionally quantifying over the underlying set. This <u>is</u> just what happens with '''[[lo'ei]]''': '''mi nitcu lo'ei tanxe''' is defined as '''mi kairnitcu le ka ce'u tanxe'''. There is <u>no</u> quantification over '''lo'i tanxe''' there, only a quantification over '''lo'i ka ce'u tanxe''', which, like every property, whether it obtains or not (or can possibly obtain), is inherently a singleton. -- [[Adam|Adam]]


I don't understand how the meaning of the bridi can be determined without quantifying over the underlying set, unless the set is one-membered. Perhaps the idea is simply that the quantifier is left unspecified so that it is glorked from context? That seems reasonable, but it's not equivalent to ''[[lo'ei|lo'ei]]'' (e.g. ''mi nitcu tu'o tanxe'' is not equivalent to ''mi nitcu lo'ei tanxe''). --[[User:And Rosta|And Rosta]]
If we think of 'sets' as groups instead (collectivities, = Lojban 'masses'), then we can just refer directly to the set/group without quantifiying over its membership. Regarding your analysis of '''tu'o''' and '''lo'ei''', I don't get it. '''lo'ei''' always seems to reduce to '''lo''' with a narrow scope within that of some implicit predicate. In other words, I think I have a rough idea of how '''lo'ei''' works, but I can't make sense of your and xorxes's analysis of its working. Maybe this discussion should move to the [[lo'ei]] page, if you're arguing that '''tu'o''' is equivalent to '''lo'ei'''. --[[User:And Rosta|And Rosta]]
* Mathematical sets cannot be used directly, and mathematical sets are what '''lo'i''' does. Also, in Lojban you cannot just use groups/collectivities/masses directly without quantification. For individual gadri ('''lo/le/la''') you must pick out (quantify over) individuals from that group. For mass gadri (''loi/lei/lai'') you must pick out (quantify over) parts of that mass. xorxes's rewrite of '''broda lo'ei brode''' to '''kairbroda le ka ce'u du lo brode''' was an intermediate step, I think, in the ultimate goal of getting to ''kairbroda le ka ce'u brode''. As xorxes says, if you don't understand that, take '''sisku''', which is a primitive in standard Lojban: '''mi sisku le ka ce'u tanxe''' (='''mi buska lo'ei/tu'o tanxe''') doesn't involve any quantification over '''lo'i tanxe''', it merely uses the meaning of tanxe as expressed in the property '''le ka ce'u tanxe''', and adds it to the predicate '''sisku'''. --[[Adam]]


;: If the set is one-membered, then you are still quantifying over that one member, though perhaps a bit trivially. I think that the idea (as [[User:xorxes|xorxes]] has expounded) is that the quantifier is deleted, resulting in the intensional meaning of the selbri being added to the main bridi without extensionally quantifying over the underlying set. This '''is''' just what happens with ''[[lo'ei|lo'ei]]'': ''mi nitcu lo'ei tanxe'' is defined as ''mi kairnitcu le ka ce'u tanxe''. There is '''no''' quantification over ''lo'i tanxe'' there, only a quantification over ''lo'i ka ce'u tanxe'', which, like every property, whether it obtains or not (or can possibly obtain), is inherently a singleton. -- [[Adam|Adam]]
I don't mean that '''lo'i broda''' is a group rather than a mathematical set. I mean that if we conceive of categories as <u>groups</u> of individuals, then we can either quantify over the membership, or refer to the group directly. (This is how '''lei/loi''' ought to work.) Regarding '''sisku''', as I've been saying in the discussions on Jboske, I don't understand '''sisku tu'o ka ce'u broda''' except as a way of expressing '''troci tu'o du'u co'e lo broda''', so for me the analogy with sisku does not help at all in explicating the notion of null quantification. I understand that '''lo'ei''' is supposed to "use the meaning of tanxe as expressed in the property '''le ka ce'u tanxe''', and adds it to the predicate '''sisku'''", but I can't make sense of this. We haven't found any examples from English that don't reduce to '''lo''' (or '''loi'e'''). --[[User:And Rosta|And Rosta]]
 
If we think of 'sets' as groups instead (collectivities, = Lojban 'masses'), then we can just refer directly to the set/group without quantifiying over its membership. Regarding your analysis of ''tu'o'' and ''lo'ei'', I don't get it. ''lo'ei'' always seems to reduce to ''lo'' with a narrow scope within that of some implicit predicate. In other words, I think I have a rough idea of how ''lo'ei'' works, but I can't make sense of your and xorxes's analysis of its working. Maybe this discussion should move to the [[lo'ei|lo'ei]] page, if you're arguing that ''tu'o'' is equivalent to ''lo'ei''. --[[User:And Rosta|And Rosta]]
 
;: Mathematical sets cannot be used directly, and mathematical sets are what ''lo'i'' does. Also, in Lojban you cannot just use groups/collectivities/masses directly without quantification. For individual gadri (''lo/le/la'') you must pick out (quantify over) individuals from that group. For mass gadri (''loi/lei/lai'') you must pick out (quantify over) parts of that mass. xorxes's rewrite of ''broda lo'ei brode'' to ''kairbroda le ka ce'u du lo brode'' was an intermediate step, I think, in the ultimate goal of getting to ''kairbroda le ka ce'u brode''. As xorxes says, if you don't understand that, take ''sisku'', which is a primitive in standard Lojban: ''mi sisku le ka ce'u tanxe'' (=''mi buska lo'ei/tu'o tanxe'') doesn't involve any quantification over ''lo'i tanxe'', it merely uses the meaning of tanxe as expressed in the property ''le ka ce'u tanxe'', and adds it to the predicate ''sisku''. --[[Adam|Adam]]
 
I don't mean that ''lo'i broda'' is a group rather than a mathematical set. I mean that if we conceive of categories as *groups* of individuals, then we can either quantify over the membership, or refer to the group directly. (This is how ''lei/loi'' ought to work.) Regarding ''sisku'', as I've been saying in the discussions on Jboske, I don't understand ''sisku tu'o ka ce'u broda'' except as a way of expressing ''troci tu'o du'u co'e lo broda'', so for me the analogy with sisku does not help at all in explicating the notion of null quantification. I understand that ''lo'ei'' is supposed to "use the meaning of tanxe as expressed in the property ''le ka ce'u tanxe'', and adds it to the predicate ''sisku''", but I can't make sense of this. We haven't found any examples from English that don't reduce to ''lo'' (or ''loi'e''). --[[User:And Rosta|And Rosta]]

Revision as of 14:34, 17 August 2019

(originally from tu'o and relevant to discussions of tu'o and lo'ei and similar creatures.)

I don't understand how the meaning of the bridi can be determined without quantifying over the underlying set, unless the set is one-membered. Perhaps the idea is simply that the quantifier is left unspecified so that it is glorked from context? That seems reasonable, but it's not equivalent to lo'ei (e.g. mi nitcu tu'o tanxe is not equivalent to mi nitcu lo'ei tanxe). --And Rosta

  • If the set is one-membered, then you are still quantifying over that one member, though perhaps a bit trivially. I think that the idea (as xorxes has expounded) is that the quantifier is deleted, resulting in the intensional meaning of the selbri being added to the main bridi without extensionally quantifying over the underlying set. This is just what happens with lo'ei: mi nitcu lo'ei tanxe is defined as mi kairnitcu le ka ce'u tanxe. There is no quantification over lo'i tanxe there, only a quantification over lo'i ka ce'u tanxe, which, like every property, whether it obtains or not (or can possibly obtain), is inherently a singleton. -- Adam

If we think of 'sets' as groups instead (collectivities, = Lojban 'masses'), then we can just refer directly to the set/group without quantifiying over its membership. Regarding your analysis of tu'o and lo'ei, I don't get it. lo'ei always seems to reduce to lo with a narrow scope within that of some implicit predicate. In other words, I think I have a rough idea of how lo'ei works, but I can't make sense of your and xorxes's analysis of its working. Maybe this discussion should move to the lo'ei page, if you're arguing that tu'o is equivalent to lo'ei. --And Rosta

  • Mathematical sets cannot be used directly, and mathematical sets are what lo'i does. Also, in Lojban you cannot just use groups/collectivities/masses directly without quantification. For individual gadri (lo/le/la) you must pick out (quantify over) individuals from that group. For mass gadri (loi/lei/lai) you must pick out (quantify over) parts of that mass. xorxes's rewrite of broda lo'ei brode to kairbroda le ka ce'u du lo brode was an intermediate step, I think, in the ultimate goal of getting to kairbroda le ka ce'u brode. As xorxes says, if you don't understand that, take sisku, which is a primitive in standard Lojban: mi sisku le ka ce'u tanxe (=mi buska lo'ei/tu'o tanxe) doesn't involve any quantification over lo'i tanxe, it merely uses the meaning of tanxe as expressed in the property le ka ce'u tanxe, and adds it to the predicate sisku. --Adam

I don't mean that lo'i broda is a group rather than a mathematical set. I mean that if we conceive of categories as groups of individuals, then we can either quantify over the membership, or refer to the group directly. (This is how lei/loi ought to work.) Regarding sisku, as I've been saying in the discussions on Jboske, I don't understand sisku tu'o ka ce'u broda except as a way of expressing troci tu'o du'u co'e lo broda, so for me the analogy with sisku does not help at all in explicating the notion of null quantification. I understand that lo'ei is supposed to "use the meaning of tanxe as expressed in the property le ka ce'u tanxe, and adds it to the predicate sisku", but I can't make sense of this. We haven't found any examples from English that don't reduce to lo (or loi'e). --And Rosta