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I figured out, after much reading of philosophy papers, what the trouble is with quantifying into belief contexts (i.e. using a variable declared in an outside prenex within the du'u bridi). It rests on whether du'u in Lojban is transparent or opaque. Cicero is Tully. That is, la kikeron. du la tulius. The predicates "me la kikeron." and "me la tulius." are true of the same (singular) object, namely Marcus Tullius Cicero, the greatest Roman orator. The sentence "la kikeron. du la tulius." is true because the contexts of "la kikeron." and "la tulius." are both *transparent*: equals can be replaced with equals *salva veritate* (preserving truth values). Now the *sentences* "Tully is bald" and "Cicero is bald", viz. la kikeron. krecau" and "la tulius. krecau" are distinct. The sentence "lu la kikeron. krecau li'u du lu la tulius. krecau" is false, because the contexts of "la kikeron." and "la tulius." are both *opaque*: equals cannot be replaced with equals *salva veritate*. What we haven't nailed down is the abstract bridi "du'u la kikeron. krecau" and "du'u la tulius. krecau"? Are these true of different (noematic) objects, or of the same object? The difference is important because Ralph, who does not know that Cicero is Tully, believes (i.e. is disposed to assent to the claim) that Cicero is bald but does not believe (i.e. withholds assent from the claim) that Tully is bald. If Lojban beliefs de dicto work like this, as seems plain, then we must conclude that lo du'u la kikeron. krecau cu na du lo du'u la tulius. krecau, because the two du'u clauses refer to different propositions. What's different about them is not the referents of the singular terms "la kikeron." and "la tulius.", but the way in which those referents are referred to (the so-called "mode of presentation"). If du'u-contexts are truly opaque, then we don't know what it means to insert variables in them that are quantified outside the du'u. But then what is the status of "da poi du me la kikeron. zo'u la ralf. krici lo du'u da krecau"? Is this true iff Ralph is disposed to assent to "Cicero is bald"? What if he is disposed to assent to "Tully is bald"? What if he is not disposed to assent to either, but is disposed to assent to "The greatest Roman orator is bald" (supposing that he has no name for this man). We don't know because the critical mode of presentation material is outside the du'u-bridi. We can't waffle on this stuff. We have to be able to establish the truth value of "lo du'u ... cu du lo du'u ..." where the ellipsized sentences are the same except for interchanging singular terms of identical referents. If we make them equal (transparency), then we can't move between beliefs and dispositions-to-assent, which seems counterintuitive and dire. If we make them opaque, we have problems with exterior restrictions on quantification: how, if at all, are they imported? -- Winter: MIT, John Cowan Keio, INRIA, jcowan@hidden.email Issue lots of Drafts. http://www.ccil.org/~cowan So much more to understand! http://www.reutershealth.com Might simplicity return? (A "tanka", or extended haiku)