{zo'e}

[Ilmen]

Hello everybody,

I would like to ask you clarifications on the meaning of the cmavo
{zo'e}, which is defined in the CLL at
https://lojban.github.io/cll/7/7/index.html
<https://lojban.github.io/cll/7/7/index.html> as meaning “the obvious
value”, “whatever I want it to mean but haven’t bothered to figure out,
or figure out how to express”.

Let's consider the following three example sentences:

• [A] {mi tirna zo'e}
• [B] {mi tirna su'o da}
• [C] {(da'o) mi tirna ko'a} (usage of a constant {ko'a} which hasn't
been assigned a value explicitly earlier)

How does [A] semantically differ from [B] and [C]? (I suspect that the
two latters ultimately mean the same thing.)
How [A] should be represented in logical notation?
{zo'e} cannot be a constant as it changes its referent(s) on each
occurrence.

The gloss “the obvious value” given in the CLL may lead one to consider
“you-know-what” or “something which you should be able to identify
easily” as a possible meaning for {zo'e}, although the second wording
“whatever I want it to mean but haven’t bothered to figure out, or
figure out how to express” doesn't seem to support it.
That second wording doesn't imply that the addressee should be able to
identify the referents of {zo'e}, but however it seems to imply that the
speaker has a more precise idea on the referents than with a plain {su'o
da}, but didn't manage or bother to lay out a more detailed description.
Therefore, {su'o co'e} (“some thing(s) satisfying the contextually
salient predicate”) or “some certain thing(s) (known by the speaker but
not necessarily by the listener)” may also qualify as candidate
definitions for {zo'e}.

What in your opinion should be a more precise definition of {zo'e}?

—mu'o mi'e la .ilmen.

[Pierre Abbat]

On Sunday, November 22, 2020 5:07:48 PM EST Ilmen wrote:
> Hello everybody,
>
> I would like to ask you clarifications on the meaning of the cmavo
> {zo'e}, which is defined in the CLL at
> https://lojban.github.io/cll/7/7/index.html
> <https://lojban.github.io/cll/7/7/index.html> as meaning “the obvious
> value”, “whatever I want it to mean but haven’t bothered to figure out,
> or figure out how to express”.
>
> Let's consider the following three example sentences:
>
> • [A] {mi tirna zo'e}
> • [B] {mi tirna su'o da}
> • [C] {(da'o) mi tirna ko'a} (usage of a constant {ko'a} which hasn't
> been assigned a value explicitly earlier)
>
> How does [A] semantically differ from [B] and [C]? (I suspect that the
> two latters ultimately mean the same thing.)
> How [A] should be represented in logical notation?
> {zo'e} cannot be a constant as it changes its referent(s) on each
> occurrence.

{mi tirna zo'e .i mi viska zo'e} is compatible with {mi tirna lo datka .i mi
viska lo gerku}, but {mi tirna su'o da .i mi viska su'o da} is not.

> The gloss “the obvious value” given in the CLL may lead one to consider
> “you-know-what” or “something which you should be able to identify
> easily” as a possible meaning for {zo'e}, although the second wording
> “whatever I want it to mean but haven’t bothered to figure out, or
> figure out how to express” doesn't seem to support it.
> That second wording doesn't imply that the addressee should be able to
> identify the referents of {zo'e}, but however it seems to imply that the
> speaker has a more precise idea on the referents than with a plain {su'o
> da}, but didn't manage or bother to lay out a more detailed description.
> Therefore, {su'o co'e} (“some thing(s) satisfying the contextually
> salient predicate”) or “some certain thing(s) (known by the speaker but
> not necessarily by the listener)” may also qualify as candidate
> definitions for {zo'e}.
>
> What in your opinion should be a more precise definition of {zo'e}?

{zo'e} is equivalent to omission (which may require a FA to keep following
arguments in the same place), except in a relative clause or abstraction,
where omission may be equivalent to {ke'a} or {ce'u}. Whether there is an
obvious value is dependent on context and pragmatics.

—le trene cu catra le bomju poi xabju le mlana be le rendargu
—mi viska zo'e
Here {zo'e} could plausibly mean {le trene} or {le bomju} or {lo pixra be le
fasnu}, but not {lo mlatu}. But if someone takes off my blindfold in a field
where there are cats, and I say {mi viska zo'e}, {zo'e} likely means {lo
mlatu}.

Pierre
--
li ze te'a ci vu'u ci bi'e te'a mu du
li ci su'i ze te'a mu bi'e vu'u ci

[Michael Turniansky]

le bomju ki'a .i  zo bomju cu xelfanva zoi gy "bum" gy xu la lojban la gliban zi'o?

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[Pierre Abbat]

On Thursday, November 26, 2020 9:15:24 AM EST Michael Turniansky wrote:
> le bomju ki'a .i zo bomju cu xelfanva zoi gy "bum" gy xu la lojban la
> gliban zi'o?

go'i .i ji'a go'i zoi .ry. бомж .ry. lo lojbo lo rusko

Many years ago, I was traveling somewhere by train, and the train hit a
(drunk?) bum who had fallen asleep on the track. The crew told us that the
train had struck debris, but the time we were stopped was too long and the
presence of police officers didn't make sense in that event. Word got out among
the passengers of what had really happened. I later made a speech about it
called "Lying on the Tracks".

Pierre

--
Don't buy a French car in Holland. It may be a citroen.

[scope845h...@icebubble.org]

Ilmen <ilmen....@gmail.com> writes:

> I would like to ask you clarifications on the meaning of the cmavo
> {zo'e}, which is defined in the CLL at
> https://lojban.github.io/cll/7/7/index.html

Formal definitions of cmavo can be found on the BPFK pages of the Wiki
at lojban.org. When I say "formal" definitions, I mean that their
meanings are defined very specifially, typically using Lojban.

Pierre Abbat <ph...@bezitopo.org> writes:

> {mi tirna zo'e .i mi viska zo'e} is compatible with {mi tirna lo datka .i mi
> viska lo gerku}, but {mi tirna su'o da .i mi viska su'o da} is not.

I don't think that's correct. IIRC, the two {da} are only synonymous
when the bridi are logically connected. So, for example, if it were
{mi tirna su'o da .ije mi viska su'o da}, you'd be correct.

Pierre Abbat <ph...@bezitopo.org> writes:

> Many years ago, I was traveling somewhere by train, and the train hit a
> (drunk?) bum who had fallen asleep on the track. The crew told us that the

That actually happened to an acquaintance of an acquaintance of mine, a
few years back. Here's one of the newspaper articles on it:

Dover Police: Man killed by train may have been a transient
Foster's Daily Democrat
Saturday, October 15, 2011
By LARRY W. BROWN
http://fosters.com/apps/pbcs.dll/article?AID=/20111015/GJNEWS_01/710159944/-1/FOSNEWS01/

Whether it was a murder or suicide was never quite sorted-out.

[Pierre Abbat]

On Wednesday, December 2, 2020 7:31:42 PM EST

scope845h...@icebubble.org wrote:
> That actually happened to an acquaintance of an acquaintance of mine, a
> few years back. Here's one of the newspaper articles on it:
>
> Dover Police: Man killed by train may have been a transient
> Foster's Daily Democrat
> Saturday, October 15, 2011
> By LARRY W. BROWN
>
> http://fosters.com/apps/pbcs.dll/article?AID=/20111015/GJNEWS_01/710159944/
> -1/FOSNEWS01/
>
> Whether it was a murder or suicide was never quite sorted-out.

I get "Unknown host archive.fosters.com". Did it happen in Dover? I'm pretty
sure the one I was talking about happened in rural North Carolina or
Virginia, not Delaware.

Pierre
--
sei do'anai mi'a djuno puze'e noroi nalselganse srera

[Ilmen]

Le 03/12/2020 à 01:31, scope845h...@icebubble.org a écrit :
> Formal definitions of cmavo can be found on the BPFK pages of the Wiki
> at lojban.org. When I say "formal" definitions, I mean that their
> meanings are defined very specifially, typically using Lojban.

I'm not seeing any formal definition (i.e. substitutional definition) at
https://mw.lojban.org/papri/BPFK_Section:_Grammatical_Pro-sumti#cmavo:_zo.27e_.28KOhA7.29
<https://mw.lojban.org/papri/BPFK_Section:_Grammatical_Pro-sumti#cmavo:_zo.27e_.28KOhA7.29>.

—Ilmen.

[scope845h...@icebubble.org]

Pierre Abbat <ph...@bezitopo.org> writes:

> I get "Unknown host archive.fosters.com". Did it happen in Dover? I'm pretty
> sure the one I was talking about happened in rural North Carolina or
> Virginia, not Delaware.

It happened in Dover, NH, not Dover, DE. That newspaper's Web site
(fosters.com) has sucked for a long time... at least 5 years. When I
visit an article on it, the aritcle consists entirely of tiny gray
squares. The URL I posted is the one that worked, back when their site
acutally worked. ;)

If you click-around, you may be able to find something about it. IIRC,
the paper ran at least three articles on it. The man's name was Steven
Wilson.

[Corbin Simpson]

u'i coi

You've buried the lede somewhat. There probably *aren't* context-free formal definitions possible for {zo'e}, because speakers usually intend either the semantics of {zi'o} (pretend that the place doesn't exist) or {su'o da} (something fills the place but it is irrelevant; it does logically exist, though!) The former is fulfilled when zero or more objects match, but the latter requires at least one object to match.

As a basic example, in the utterance {mi vecnu zo'e}, am I asserting that at least one sale takes place? (Ignoring temporal issues.)

[scope845h...@icebubble.org]

Corbin Simpson <mostawe...@gmail.com> writes:

> You've buried the lede somewhat. There probably *aren't* context-free
> formal definitions possible for {zo'e}, because speakers usually intend
> either the semantics of {zi'o} (pretend that the place doesn't exist) or
> {su'o da} (something fills the place but it is irrelevant; it does
> logically exist, though!) The former is fulfilled when zero or more objects
> match, but the latter requires at least one object to match.
>
> As a basic example, in the utterance {mi vecnu zo'e}, am I asserting that
> at least one sale takes place? (Ignoring temporal issues.)

I think just about all of that is wrong. {zo'e} can never mean {zi'o}
but {zo'e} can, in certain contexts, mean {noda}. If you and I are in a
brightly-lit room when the power goes out and it's suddenly plunged into
pitch-black darkness, I might reasonably utter the observative:

viska

meaning, in that context, "I can't see anything!", {mi viska noda}.

[Jacob Thomas Errington]

On 2021-01-01 18:07, scope845h...@icebubble.org wrote:

> I think just about all of that is wrong. {zo'e} can never mean {zi'o}
> but {zo'e} can, in certain contexts, mean {noda}. If you and I are in a
> brightly-lit room when the power goes out and it's suddenly plunged into
> pitch-black darkness, I might reasonably utter the observative:
>
> viska
>
> meaning, in that context, "I can't see anything!", {mi viska noda}.

{mi viska noda} is the same as {mi na viska su'o da}, so if what you're
saying is true, then we can't know except through context whether a
statement is affirmative or negative. Instead, use the observative {na
viska}.

A zo'e-like word (e.g. do'e, xo'e, etc.) shouln't be able to stand for
something that makes the claim go from affirmative to negative or vice
versa.

[Ilmen]

Does {ro gerku be da cu gerku (zo'e)} imply {su'o de zo'u ro gerku be da
cu gerku de}, that is, that all dogs are of the same breed? This
implication should hold if {zo'e} stands for a constant*. This is a
perspicacious question Robin Town has raised today to me.

(* Each occurrence of {zo'e} would stand for an anonymous constant, as
each of its occurrences may refer to something different.)

—Ilmen.

[scope845h...@icebubble.org]

Jacob Thomas Errington <ja...@mail.jerrington.me> writes:

> {mi viska noda} is the same as {mi na viska su'o da}, so if what
> you're saying is true, then we can't know except through context
> whether a statement is affirmative or negative. Instead, use the
> observative {na viska}.
>
> A zo'e-like word (e.g. do'e, xo'e, etc.) shouln't be able to stand for
> something that makes the claim go from affirmative to negative or vice
> versa.

If we use your interpretation, then {mi viska zo'e} could mean {mi viska
lo nanmu} but could not mean {mi viska lo na nanmu}. It seems, to me,
that {lo na nanmu} would be a perfectly legitimate meaning for {zo'e}.

zo do'e ki'a

[Adam Lopresto]

{lo na nanmu} is still a thing (that is, it's still compatible with {su'o da} and not with {no da}), so there's no problem with {zo'e} reflecting it. It's a thing that doesn't {nanmu}, but it still has to be something. {lo na nanmu} successfully killed the Witch-King of Angmar. 

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[Corbin Simpson]

Note that {lo na} implicitly summons and invokes the Law of Excluded Middle, as do many of these {no}/{na} rules. {lo na nanmu} first imagines that there exists a collection of everything (questionable; is it a set?), as well as a collection of all nanmu1 (must exist, by definition of relations; in fact, it's a set!), and then takes the difference between those collections (which might not be a set), and finally performs a choice, requiring the full Axiom of Choice (because the collection is so big!), to select something. The selection might be impredicative; how can you show that the "everything" which is being ranged over is *actually* being considered for selection?

[Adam Lopresto]

I don't think it's anywhere near that complicated. {lo na nanmu} just summons those things that satisfy {na nanmu}. If I spelled it {narnanmu} would that make it more obvious that it's not doing anything hugely elaborate? 

To view this discussion on the web visit https://groups.google.com/d/msgid/lojban/e61dc0af-1a6b-45b4-9930-acccd73a1a41n%40googlegroups.com.

[Jacob Thomas Errington]

coi

On 2021-01-06 13:04, scope845h...@icebubble.org wrote:
> If we use your interpretation, then {mi viska zo'e} could mean {mi viska
> lo nanmu} but could not mean {mi viska lo na nanmu}. It seems, to me,
> that {lo na nanmu} would be a perfectly legitimate meaning for {zo'e}.

My interpretation wouldn't forbid {lo na nanmu} as a referent for
{zo'e}. It forbids {no da (poi whatever)} as a referent for zo'e,
because such a referent makes the (outer) bridi negative.

  {mi viska lo na nanmu} is an affirmative statement, that I see
something that satisfies (the negative) {na nanmu}.

On the other hand

  {mi viska no (da poi) nanmu} is a negative statement, that I do not
see anything that satisfies (the affirmative) {nanmu}.

The crucial difference is that in the former, I do say I'm seeing
something, and that thing is identified by not being a {nanmu}; whereas
in the latter I am merely denying seeing any {nanmu}. In other words,
the latter is a claim of _not seeing_, versus the former being a claim
of _seeing_.

See
https://lojban.org/publications/cll/cll_v1.1_xhtml-section-chunks/section-negation-boundaries.html#example-random-id-fpeW
in particular the paragraph below example 16.70 explaining that {no da}
is replaced with {naku su'o da}.

Now I hope my reason for saying {no da (poi whatever)} can't be what
{zo'e} stands for is clear: if (implicit) {zo'e} can stand for {noda},
then a claim such as {mi viska (zo'e)} could actually mean that I
_don't_ see! And to me, that is totally bonkers.

> zo do'e ki'a

Many cmavo ending in {o'e} are 'elliptical' in Lojban (with the
egregious exception of {.o'e} itself). {do'e} is the elliptical modal,
which stands for some BAI/fi'o.

.i mi'e la tsani mu'o

[scope845h...@icebubble.org]

Jacob Thomas Errington <ja...@mail.jerrington.me> writes:

>   {mi viska lo na nanmu} is an affirmative statement, that I see
> something that satisfies (the negative) {na nanmu}.

By your interpretation, would the following two bridi mean the same
thing?

.i mi viska lo na nanmu

.i mi viska lo na'e nanmu

They'd both be saying that you see something other than a man.

[Mark E. Shoulson]

But they don't mean the same thing.  {lo na nanmu} is not the same as {lo na'e nanmu}.  {lo na nanmu} is a thing that doesn't {nanmu}.  But {na'e} is a *scalar* negator, not a logical one.  It implies some sort of scale of {nanmu}itude (lo ni nanmu), and says that what you're seeing is on the negative side of it.  Exactly what that would mean I'm not sure I could say for certain.  Is the scale {nanmu}↔{ninmu}?  In that case, a woman would be {lo na'e nanmu} as well as {lo na nanmu}, but a rock is {lo na nanmu} but not {lo na'e nanmu}.  But the scale here is not obvious.

~mark

[Jacob Thomas Errington]

No, these have interpretations that are different, based on how {na} and
{na'e} are different. Both statements are however affirmative.

For example, {lo karce na nanmu} seems pretty reasonable. {lo karce cu
na'e nanmu} on the other hand is much stranger. {na'e} is a scalar
negation, so we have to imagine some scale on which to put "nanmu" and
then imagine what the opposite of that is. So maybe it means something
more like "unmasculine" as opposed to plainly "not a man".

So if I said, {mi viska lo na nanmu} that just means I saw something
that is not a man. Maybe a car, or a dog, or a chair. But if I said {mi
viska lo na'e nanmu}, I think the interpretation would be that I saw
someone who appears unmasculine in some way.

[scope845h...@icebubble.org]

"Mark E. Shoulson" <ma...@kli.org> writes:

> But they don't mean the same thing. {lo na nanmu} is not the same as {lo
> na'e nanmu}. {lo na nanmu} is a thing that doesn't {nanmu}. But {na'e}
> is a *scalar* negator, not a logical one. It implies some sort of scale
> of {nanmu}itude (lo ni nanmu), and says that what you're seeing is on the
> negative side of it. Exactly what that would mean I'm not sure I could

> say for certain. Is the scale {nanmu}<->{ninmu}? In that case, a woman

> would be {lo na'e nanmu} as well as {lo na nanmu}, but a rock is {lo na
> nanmu} but not {lo na'e nanmu}. But the scale here is not obvious.

I think you're misunderstanding the different types of negation in
Lojban. Compare:

.i mi viska lo na nanmu

.i mi viska lo na'e nanmu

.i mi viska lo no'e nanmu

.i mi viska lo to'e nanmu

[Mike S.]

Just a couple tentative thoughts on this old thread.

On Sun, Nov 22, 2020 at 5:07 PM Ilmen <ilmen....@gmail.com> wrote:

Hello everybody,

I would like to ask you clarifications on the meaning of the cmavo
{zo'e}, which is defined in the CLL at
https://lojban.github.io/cll/7/7/index.html
<https://lojban.github.io/cll/7/7/index.html> as meaning “the obvious
value”, “whatever I want it to mean but haven’t bothered to figure out,
or figure out how to express”.

Let's consider the following three example sentences:

• [A] {mi tirna zo'e}
• [B] {mi tirna su'o da}
• [C] {(da'o) mi tirna ko'a} (usage of a constant {ko'a} which hasn't
been assigned a value explicitly earlier)

How does [A] semantically differ from [B] and [C]? (I suspect that the
two latters ultimately mean the same thing.)

I think you're right about [B] and [C] as full sentences -- with the {da'o} in front, there seems to be no possible world in which one is true (or false) and not the other.  And if two propositions have the same truth value in all possible worlds, then they must have the same truth-conditions, and therefore the same meaning.  I believe this logical equivalence is reflected in a standard rewriting/transformation rule called existential instantiation (a.k.a existential elimination) which allows you to replace an existential quantifier and its variable with a constant under certain conditions.  And there is a rewriting rule that goes in the opposite direction called existential generalization (a.k.a. existential introduction).

https://en.wikipedia.org/wiki/Existential_instantiation

https://en.wikipedia.org/wiki/Existential_generalization

So it's not surprising that this is a confusing issue.  In a lot of cases, whether you choose an existential quantifier or a constant does not matter much.

However, assuming that {ko'a} is unquantified and presupposed, then I do not believe [B] and [C] are freely interchangeable in practice as *nested* propositions.  For example, under negation:

• [B1] {naku mi tirna su'o da}

I don't hear anything.

• [C1] {(da'o) naku mi tirna ko'a}

I don't hear [whatever it is I don't hear].

It seems to me that the {naku} causes a pragmatic difference to surface -- [B1] is a universal claim based on the dual nature of {su'o} under de Morgan's laws, while [C1] invites the listener to try to pick out a salient value.  And although perhaps {ko'a} could in principle mean something like "the whole domain of discourse", that would not be very cooperative, given that {su'o da} is available.

When forming questions it seems a similar difference surfaces:

• [B2] {xu do tirna su'o da}

Do you hear anything (at all)?

• [C2] {(da'o) xu mi tirna ko'a}

Do you hear it?

We shouldn't be too surprised to discover these differences; {su'o} seems to be about plugging in totally arbitrary values, or it could be conceived as a way to generate an iterated logical-disjunction of (a possibly infinite number of) propositions, in the same way that summation with capital sigma is iterates over addition); {ko'a} is much more like an anaphor for a certain semantic value, whether we know what it is exactly or not -- whatever it is though, it's not quite arbitrary.

I think there are three possibilities for defining {zo'e}:

1. {zo'e} means {da'o ko'a}, at least at first glance.

2. {zo'e} means {su'o da}.

3. {zo'e} means either depending on context.

It's not hard to find examples that pull us both directions, given usual contexts:

D {mi na djuno [zo'e]}

pulls us toward {da'o ko'a} (option 1).

E. {mi na mlatu [zo'e]}

pulls us toward {su'o da} (option 2).

The xorlo-izing BPFK definition of {lo} makes options 2 and 3 problematic, and so ultimately, it seems to me like the choice should be option 1.  The problem, however, is that it would probably necessitate debloatification and/or polymorphism for many existing predicates (entailing a change to official definitions), to avoid undesirable "na mlatu" sentences.  Or maybe, teach people to say {mi mlatu no da} instead of {mi na mlatu}.   Or maybe just tolerate some rather odd pragmatics.  (BTW the community is the boss; I am just giving an opinion.)

How [A] should be represented in logical notation?

In the simplest cases, {zo'e} could be represented by an unbound symbol, say the letter theta, subscripted with sequential integers for each appearance.  The rule of interpretation would be that theta-symbols pick out whatever works. Some people would say there is a hidden existential quantifier in there, but I say no, it's a constant-like symbol with a presupposed value determined by context. 

Another device increasingly used in formal semantics is the choice operator, borrowed from Hilbert, represented by curly lowercase epsilon, which I'll skip describing for now.

 

{zo'e} cannot be a constant as it changes its referent(s) on each
occurrence.

Yes, ultimately, {da'o ko'a} probably isn't adequate; {zo'e} has to be some kind of function that changes meaning depending on context and even takes arguments; that's sensitive to quantifiers (allowing it to take multiple values with {ro}, as Martin Bays pointed out once on the list); and yet also impervious to the scope of {naku}.   Maybe something like Skolem functions, as Guskant suggested, though how exactly to formalize this for a logical notational rewriting for Lojban (or for any other loglang) remains to be seen (I can't remember how Martin did it).  Maybe something like:

ro remna cu prami zo'e

[∀x remna(x)] prami(x, zohe(x))

Where {zohe} here is not a predicate but a contextually determined function from entities to entities.

mi'e .maik.

mu'o

[Ilmen]

• [B1] {naku mi tirna su'o da}

I don't hear anything.

• [C1] {(da'o) naku mi tirna ko'a}

I don't hear [whatever it is I don't hear].

I think the equivalence should be ⟪su'o da zo'u naku mi tirna da⟫ = ⟪(da'o) naku mi tirna ko'a⟫ (as top-level sentences), i.e. with ⟪su'o da⟫ taking the topmost scope. Actually it should even scope over the illocution of the sentence (i.e. assertion, question, command…), because, as you shown in your example sentences with the interrogative illocutionary marker ⟪xu⟫, ⟪da⟫ is bound under the scope of ⟪xu⟫, unlike ⟪ko'a⟫. A better equivalence would therefore be:
⟪ca'e mi do brireisku be lo ka (ce'u) jezyje'u lo du'u do tirna ko'a⟫
= ⟪ca'e su'o da zo'u mi do brireisku be lo ka (ce'u) jezyje'u lo du'u do tirna da⟫

As for the interpretation of ⟪zo'e⟫ as a function as you suggested, this is reminiscent of the experimental cmavo ⟪zo'ei⟫, by the way.

—Ilmen.

[Mike S.]

I am going to start from the beginning because I think I slightly misspoke.

• [A] {mi tirna zo'e}
• [B] {mi tirna su'o da}
• [C] {(da'o) mi tirna ko'a} (usage of a constant {ko'a} which hasn't
been assigned a value explicitly earlier)

How does [A] semantically differ from [B] and [C]? (I suspect that the
two latters ultimately mean the same thing.)

Instead of "logically equivalent", I think what I should have said is that B can be inferred (i.e. existentially generalized) given C, but C can be inferred (i.e. existentially instantiated) given B _only_ if {ko'a} is an unused symbol without "baggage" restrictions.  I know that {da'o} clears KOhA-assignments, but it's possible that KOhA acquires new ones as soon as you use them, even without {goi}.  The question is, what exactly does {ko'a} after {da'o} without {goi} mean?  I see two possibilities for {(da'o) mi tirna ko'a}:

C(a): = {(da'o) su'o da zo'u mi tirna da goi ko'a}
"I hear something -- call it X".
(Effect: Something unspecified, except that I hear it, is assigned a constant.)

C(b): = {(da'o) mi tirna zo'e goi ko'a}
"I hear [it/obvious value/whatever I hear] -- call it X"
(Effect: Something at least potentially specified by context is assigned a constant.)

It's not clear that the truth-conditions of C(a) and C(b) are the same.  The first is true if I hear anything, and the second is true -- at least potentially -- only if I hear the thing which is specific to the context.  

I'll stop here for today.  The CLL doesn't say how to interpret an unassigned {ko'a}, but implicit {zo'e goi} seems to fit both the usual logic of place-defaults as well as the spirit of {ko'a}, since {ko'a} is usually assigned to specific entities.