This is the lexemic element, represented by a pause in speech or a comma in writing, which has survived the preparser's inspection of its context and has been found to be genuinely lexemic, that is, necessary for the parser to be told about. The two written expressions of PAUSE are as a comma [,] and as a pound-sign [#]. Pauses come to the preparser as [,]s. The preparser then removes all instances of [,] which are not lexemic, i.e., which, like the morphemic pauses after name-words or before vowel-initial connectives, do not actually figure in the grammar rules, and rewrites the others as [#]s. Only [#]s occur in the preparsed strings which are delivered to the parser.
Lexeme PO: Abstraction Operators
There are exactly two of these, the event-abstractor po, and the property abstractor pu. There is a third abstractor, zo, which abstracts quantities; but because pseudo-instances of zo are occasionally generated while making acronymic PREDAs, the preparser, which must identify these kinds of PREDAs, requires that zo have its own lexeme; see ZO. This is a consequence of the fact that /z/ is the acronymic hyphen. So CIO is CaiIzO, which the preparser will read as a compound formed of the lexemes TAI + I + ZO and then classify it as a PREDA. Thus the preparser uses ZO in its lexing operations. If it weren't for this, zo would be a member of PO, which it is like in all grammatical respects.
The two PO words and ZO occur in 3 contexts: (1) Close-bound or "short-scope" PO/ZO occurs just before a predicate word or predunit, and in this context the scope of the abstraction is just that single word or predunit; e.g., Da po sucmi ditca = 'X is an act-of-swimming teacher', presumably one who teaches that activity. It should not be inferred that abstraction is necessary here. This same claim can be made with the shorter concrete metaphor in Da sucmi ditca = 'X is a swim(mer) teacher', and loglanists generally prefer these concrete forms. Where precision is needed, however, the Da po sucmi ditca metaphor is available to the loglanist just as the gerund with '-ing' is available to the anglophone…and with perhaps less ambiguity about what is intended. (2) Long-scope PO/ZO occurs when it is followed by either (2a) a pause-comma or a gu, in which case the scope of abstraction is the entire ensuing predicate expression, including any arguments, e.g., Da po, sucmi ditca lo frasa = 'X is a case of being a swimmer teacher of French' (perhaps one who teaches French while swimming?), or (2b) either an argument or a modifier, in which case no other mark is needed to tell the parser that the PO has long scope; e.g., Da po de sucmi ditca lo frasa = 'X is a case of Y's being a swimming teacher of French'. In both these contexts, the operand of PO/ZO is a sentence, even though it may be a sentence without arguments—i.e., an unspecified imperative—in context (2a). (3) PO/ZO also occurs in LEPO compounds (q.v.); in this descriptive context the abstraction is always long-scope; e.g., Lepo de sucmi ditca lo frasa = 'The event of Y's swim-teaching French'.
The semantic distinction between po and pu, between what we call in English "events" and what we call "properties", is perhaps the most difficult to understand in Loglan. The difference between these two operations is clearest in the descriptive context, that is, between the designate of event-descriptions and those of property-descriptions as abstracted, let us say, from the same predicated relationships. Any differences found here should apply, of course, to the other contexts. Let us examine, then, both an event-description and the property-description abstracted from the same relationship.
Lepo evidently abstracts a case, state, condition or event of any length—as long as an epoch or as short as a sneeze—from some predicated relationship. Lepu, in its turn, may abstract a property or quality from the same relationship. Suppose the predicated relationship is a motherhood between a mammalian mother X, an offspring Y and a father Z. We note first that the event-descriptions abstracted from such relationships are time-bound; like stories, mammalian motherhoods have beginnings, middles, and ends, and can apparently involve substantial segments of the "life-lines" of several or even many individuals. On a common understanding of motherhood, this one will involve those segments of X's and Y's lifetimes from the moment of her conception of Y and either her death or Y's, whichever is earlier. Of Z's lifetime, at least in many mammalian species, only a brief snippet need be considered to be part of X's motherhood, namely that snippet in which his sperm was delivered to her in some fashion. Of course more may be involved; in species in which pair-bonding takes place, more is involved. But this is sufficient to describe the event-state-condition of motherhood in mice, for example. We note that the thing that lepo designates about these 3 individuals is laid out in space-time. It has a beginning, a duration and an end. And the relevant segments of each of the three life-lines describe paths through space as well.
The property description of this same relationship, in contrast, is essentially time-free. It is the least set of facts which would establish the truth of that predicated relationship if it were true. That Y developed from an ovum produced by X's ovarian tissue is one of them; that that ovum was fertilized by a spermatazoan produced by Z's testicular tissue is another one. Are there any others? It would seem not. These two properties of these three individuals would, if known, be sufficient to establish X's maternity of Y by Z in any court of law…or, more likely, in any laboratory. And that, it would appear, is what a property is: it is that lean abstraction from the richness of the world that is just sufficient to enable us to know the truth of some matter.
The event-description is, in contrast, a "fat" concept. The designata of descriptions like lepo da mamla matma de di ('The event-state-condition of X's mammalian motherhood of Y by father Z') are often rich and complicated segments of the world; and they have a richer dimensionality than properties do. They have duration, for example, as properties do not. The designatum of lepu da mamla matma de di ('The property of X's mammalian maternity of Y by father Z') consists, in contrast, of two very simple but sometimes difficult to establish facts; and those facts are strangely free of time and other complications.
In sum, designata of po-abstractions are rich, multi-dimensional objects distinguished by duration; the designata of pu-abstractions are least sets of sufficient facts. The designata of zo-abstractions are the leanest of all, of course, being simply numbers…and sometimes uninteresting numbers at that. While the amount of heat in this room, and the amount of blue in that painting may well be interesting numbers, lezo da mamla matma de di is not. How shall we measure the quantity of mammalian motherhood, as it relates to three specified individuals? Give it one if it obtains between them, zero otherwise? Not a fruitful enterprise. If one or more of the three required participants remains undesignated, however, then the number lezo da mamla matma, the amount of mammalian motherhood in which X is involved, for example, might have some interest.
In short, the zo-abstraction is the least widely applicable of the three abstractions. Zo is useful only with those properties or relations which science has managed to quantify in some way. Thus, until we know how to measure the blueness of a painting or the motherness of an animal, lezo ta blanu and lezo ta matma will have designata we will not know how to find.
Lexeme PREDA: Predicate Words
Predicate words, while the most numerous items in any lexicon—they comprise about 80% of the Loglan dictionary at the present time—are called by only two grammar rules, R21-2. PREDA words enter the grammar through this narrow window in the rule group called "predicate units", and as predunits they are then variously elaborated as the noun-like structures of Loglan, the arguments, and the verb-like ones, the predicates. But because they all enter through the same narrow window, any predicate word may end up being either.
Morphologically, PREDA words come in five varieties:-
(1) The CC-bearing, V-final words of the lexicon like preda itself. These range from short borrowed words like iglu to long complex predicates like rojmaosenmao ('agronomist'). All PREDAs of this kind are identified by the lexer. They are by far the largest group of PREDA words that have actually been built so far; they include noun-like predicates like mrenu ('is a man'), verb-like ones like godzi ('goes from…to…by route…'), adjective-like ones like corta 'is shorter than…by amount…'), preposition-like ones like bitsa ('is between…and…'), and adverb-like ones like mutce ('is extreme in dimension…' which is more frequently used as an adverbial modifier of other predicates, as in Da mutce sadji = 'X is very wise'). Loglan makes no grammatical distinction whatever between these various kinds of predicate words…as is attested by their being members of the same lexeme.
(2) The numerical predicates made with the suffixes -ri and -ra which are members of the RA Lexeme; the exact compounding formula for these kinds of PREDAs is NI/RA (+ …) + RA. This formula generates the two infinite sets of the ordinal and cardinal numbers, respectively, e.g., neri = 'is first in sequence…' and nera = 'is a monad', as well as certain irregular numericals like sutori ('is second or subsequent in sequence…') which are so much more efficient than the English circumlocutions which they translate that they have already crept into the English speech of some loglanists.
(3) The 6 predicate variables, which are two sorts: bua bue buo buu, the non-designating predicate variables used in logic (Raba rabe rabua goi ko ba bua be ki be nu bua ba = 'For every x, y, and predicate P, x P y if and only if y nu P x'); and dui dua, the demonstrative predicate variables, or "proverbs" as they are sometimes called in English grammar, which have meanings much like English 'do'. For example, 'He meant to go; and he did'. This sentence could be rendered into Loglan as Da moi godzi, ice da dui. Like all demonstratives, the i-final member of the pair is used for proximate items, whether in time or space, the a-final one, for distant items.
(4) Acronymic PREDAs such as CaiIzO [CIO]; these may be made or borrowed at will by the user. Some Loglan acronyms, like DNA and USA, have simply been borrowed from existing acronyms in the natural languages…but of course they are then repronounced as Loglan words. Thus DNA in Loglan text is the abbreviation of the compound Loglan word DaiNaiA, and USA is short for USaiA. Acronymic predicates may also be derived internally, that is, from commonly used Loglan phrases whose frequency of use may have increased so much that the Zipf principle (that the length of a linguistic expression be inversely proportional to its frequency of use) will insist that a short Loglan expression be found for it. The increasing frequency of use of long, usually technical expressions (e.g., 'deoxyribonucleic acid') is, of course, the chief cause of acronym-formation in both the natural languages and in Loglan.
It is worth noting in passing that, while the part of speech of a compound letter-word, such as MaiTai [MT], is that of an acronymic PREDA, a single letter-word, such as Mai or Tai, is classified as an instance of Lexeme TAI, the letter-variables. Letter-variables, in turn, are one of the elemental forms of the Loglan argument. So a large grammatical shift takes place in the movement of Mai to MaiTai; see Lexeme TAI for further discussion of this point.
Finally, (5), there is the predicate interrogative he, which is of course also a member of the PREDA lexeme. He may be used in all places where any other PREDA may be used:- As a modifier: Da he forli = 'X is how strong?'; as a modificand: Da mutce he = 'X is very what?'; as the entire predicate expression: Tu he = 'You're what?' or 'How are you?; as the entire utterance: He = 'What?', often used in the sense of 'What did you say?' A more polite form of the last expression is Eo he = 'Please, what?'
In conclusion, the predicate words of Loglan are of an immense number and variety; but all of them have exactly the same grammar. To know how to use one of them is to know how to use them all.
*Lexeme RA: Numerical Predicate Suffixes
There are two of these, ra ri, and both are used both as ordinary NI words and to form the numerical predicates among the PREDAs. If it weren't for the use of Lexeme RA by the preparser, which must lex these numerical predicates by analyzing them as little word compounds, ra ri would, like their companions re ro ru, be allolexes of NI.
Lexeme TAI: Letter Variables
There are exactly 100 of these letter variables in Loglan, 52 of them are words for the Latin characters, 26 upper-, and 26 lower-case; and 48 of them are words for the Greek characters, 24 upper-, and 24 lower-case. In the sequel, the word 'letteral', which is an analog of 'numeral', will stand for the phrase 'letter character'. Thus, just as  is the numeral for the number-words 'one' and ne, so [t] is the letteral for the letter-words 'tee' and tei. For their construction, see Secs. 2.21-23.
All letter-words are members of the TAI Lexeme. TAI enters the grammar at just two points, in rules R79 and R81. In R79 TAI words enter as simple arguments, as in such utterances as Tai mrenu = 'Tee is a man'; in R81, they enter as the operands of the numerical descriptor lio, as in Lio Tai numcu = '(The number) Tee is a number', for this, too, is a possible use of a letter-variable. As arguments, the uses of TAI words are very similar to those of DA words, the replacing and personal variables, etc. Like DA words, TAI words may be used as possessives in LE + TAI compounds, e.g., Letei kapma = 't's hat'. Other compounds made with TAI are the dimensioned numbers formed by NI + TAI, e.g., Sai corta Tai lio nemakeimei = 'S is shorter than T by 100km (that is, by 100 kilometers)'. The word nemakeimei is, of course, a member of NI. A final use of TAI words in compounds is to make acronymic PREDAs; these are often strings of TAI or A words interspersed with NI words, the latter being confined to non-initial positions: e.g., HaitoSaiOfo [H2S04]. Sometimes the morphological rules call for one or more instances of interstitial -z-, the acronymic hyphen, e.g., as in CaiIzO; see Sec. 2.29 for a fuller account of the construction of acronymic PREDAs.
Since simple TAI words are arguments and compound ones are predicates, this leads to a grammatical problem for the chemical abbreviations, some of which are simple TAI words, e.g., Sai or [S] for Sulphur, and others compound, e.g., Caiza or [Ca] for Calcium. This means that Da Caiza is a legitimate sentence (meaning 'X is Ca (i.e., Calcium)') but that Da Sai is not. In fact, Da Sai is a pair of arguments, perhaps an ordered couple, best translated 'X, S'. This lack of grammatical parallelism between the simple and compound letter-words is unfortunate, but it appears to be necessary and is easily accommodated. 'X is Sulphur' can be easily said symbolically in Loglan by the addition of another syllable: Da meSai. Thus the predifier ME (q.v.) turns the argument Sai into a predicate form.
Assigning the simple TAI words to one lexeme and the compound ones to another is justified by the fact that doing so leads to two very considerable conveniences, surrendering either of which would make the language poorer. One convenience is that if simple TAI words are arguments, then a rich and virtually limitless mechanism of "anaphora" (replacement of long designations by short ones) is made available to the loglanist, with the result that even ordinary Loglan speech may very well become "mathematized”: Ama pa donsu Bai, Cai = 'A gave B (gift) C', or A pa donsu B, C in the letteralized written form. We may expect that eventually such usages will exploit the full set of 100 Loglan letter variables. To give up this elegance by making simple TAI words predicates (whence *Le Ama pa donsu le Bai le Cai) would be to abandon this potentially powerful Whorfian experiment before it had been tried. So this convenience argues that at least the TAI words should be arguments.
A second and opposite convenience is assured if acronyms, which are nearly always compound letter-words, are treated grammatically as predicates. If this is done, then those acronyms which arise to fill the Zipfean need to shorten originally long predicate expressions—for example, as 'DNA' shortens 'deoxyribonucleic acid'—may be used in exactly the same ways as the longer expressions they replace. Thus, 'That's DNA' will replace "That's deoxyribonucleic acid'; and in Loglan the same abbreviation will be Ta DaiNaiA. To make acronyms arguments, would be to undo this elegance. It would require that acronyms be prefixed by the predifier me- whenever their naturally predicative role was required—which would be very frequently. Thus, *Da meDaiNaiA would be the required form for the predicate 'is an instance of DNA'; and again a useful elegance would be lost.
The solution adopted preserves both elegances. But it requires that when acronyms are used in designations, they be treated as the operands of some descriptor. Sometimes lo is the best descriptor, as in Donsu mi leva batpi je lo DaiNaiA = 'Give me that bottle of DNA'. But sometimes la is best, as in La USaiA groda gunti = 'The USA is a big country'. It depends entirely on whether, in the given context, the designation so generated is meant to be unique or not. The English description 'the USA', like its parent phrase 'the United States of America', is nearly always meant as a unique designation; therefore its translation into Loglan should probably be graced with la. Loglan makes such intentions explicit.
As mentioned, when it is desired to use a letter-word as a predicate, it must first be predified by me; see Lexeme ME.
Lexeme UI: Free Modifiers
These are the words which, unless initial in an utterance, are counted by the preparser as "grammatical noise". So UI words (along with several other items discussed at the end of this section) are removed by the preparser from the string to be parsed. They are restored to it by the postparser after the string has been parsed. We are justified in effecting this temporary removal of noisy elements from the string given to the parser because free modifiers are literally free to appear anywhere in any utterance, and so their appearance somewhere in a certain utterance gives no grammatical information about it. Free modifiers are therefore almost purely semantic devices. Their restoration after parsing assures that their semantic information will not be lost.
The entire grammatical significance of a UI word therefore lies in whether it appears at the head of its utterance or within it. When a UI word appears at the head of an utterance, it is taken to modify that utterance as a whole (Ia mi ditca = 'Certainly, I am a teacher'). When one appears non-initially, it is taken to modify the individual word it follows: Mi ia ditca = 'I, certainly, am a teacher (I don't know about the others)'; Mi ditca ia = 'I teach, certainly (I'm not sure what else I do)'. To follow a word with a free modifier is often to emphasize it. Thus the last two utterances might well be spoken /MIiaDITca/ and /miDITcaia/, respectively, while the first, with its free modifier in the Loglan-normal initial position, might receive no emphatic stress at all: /iamiDITca/.
UI words are of five semantic types: First, there are the attitudinals, which are used to express rather than report the speaker's attitude toward what da is saying, or toward some aspect of the world that is evoked by what da says. Second, there are the discursives. These are the words that call attention to how the units of the speaker's discourse are related to one another, or to the utterances of another speaker. Third, there are the relative interrogatives, the 'When?' 'Where?' 'How?' and Why?' series made by compounding any PA word with HU. Fourth, there are the utterance ordinals made by compounding any NI with FI. Finally, there are the salutations. These are the greetings, farewells, and expressions of gratitude and acknowledgement. All five kinds of UI words may be placed anywhere in an utterance, although unless special emphasis is intended, the initial position is stylistically preferred.
In general, UI words are extralogical; that is to say, they do not alter the truth-values of the sentences which they adorn. For a speaker to be convinced that da came, or to ask why da came, has no bearing on whether or not da came.
Now, in detail: -
Attitudinals. All attitudinals are VV-form words; all the VV-form words in Loglan are attitudinals except ie, the identity interrogative. The exceptional ie is more grammatically constrained than the other VV-form words but is related to them semantically, as the act of interrogating expresses an attitude; see Lexeme IE. The current list of simple attitudinals is:-
Yes, I nope so/that/to…
Yes, I will/intend to… (-ai is also L. u.c. cons. suff.)
Yes, I want to… (-ao is also Gk. u.c. cons. suff.)
I don't care whether…
Let's…/I suggest that…
Is that so?/Is it true that…? (-ei is also L. l.c. cons. suff.)
Note that several VV-forms are still unassigned: aa ee oo. These may yet be given meaning as loglanists learn how to handle these disyllables which to anglophones still seem odd.
To expand the domain of attitudinal expression, any number of compound attitudinals may yet be constructed. For example, uiua has a clear meaning: pleasure + completion = satisfaction; ueui also has a clear interpretation…and a usage; for example, it might be used to greet a long-lost friend standing at one's door. But few of these attitudinal compounds have been made. Again, the loglanist is invited to explore a new semantical domain.
Discursives. All the discursive UI words are CVV in form; but by no means all the CVV-form words are members of the UI Lexeme. For example, all of the case-tags (DIO), most of the letter variables (TAI), and many of the modifying prepositions (PA) are also of CVV-form. So there is some potential for confusing CVV-forms that seem to have similar functions. The way to distinguish the discursive UI words from the prepositional PA and DIO words is to ask whether the word you're uncertain about may be used prepositionally. If it may be, it's probably either a PA word or a DIO word. If not, it's almost certainly one of the discursives.
But what about the many words with vaguely "adverbial" meanings? If the word in question changes the claim of the predicate of the sentence in which it occurs, it's probably a PA word; a further test is whether you can turn it into a preposition. But if the word in question seems to relate the utterance as a whole to some other utterance, stated or implied, it's probably a discursive.
Here is the current list of discursive UI words. Note that none of them may be used prepositionally, that the meanings are generally adverbial but that each such adverbial meaning seems to appeal either explicitly (cia) or implicitly (coa) to another utterance or, like feu, to allude to outside information:-
For example/By way of illustration (cf. gea)
However/In contrast/On the other hand
Changing topics/(New paragraph)
Similarly/Like the foregoing
Hence it is probable that
Given/By hypothesis/Per assumption
And vice versa (reverses the order of terms in a previous claim to form a new one)
In fact/Actually/According to the facts
In particular/As an instance (cf. bea)
Generally/Generalizing from the above
Anyway/Anyhow/In any case/event
In detail/Closely examined
Skipping details/Without going into details
Notice that, like the DIO words, when a natural derivation of the discursive from its primitive mnemonic yields a TAI word, then the final vowel of that first derivative is changed to /u/. Dau and leu illustrate the /u/-transformation in the above list. What this means is that TAI words have derivational precedence over other CVV-form words.
Relative Interrogatives. These are the compounds made from any PA word plus the argument interrogative HU ('Who?'). The meanings of such compounds are always readily decipherable, since they are nothing more than contractions of prepositional phrases in which the object of the preposition, its operand, is always hu. So nahu means 'At what time?' or 'When?'; vihu means 'In or at what place?' or 'Where?'; biuhu means 'In what manner?' which is one of the many varieties of 'How?' (nearly any modal operator will fit here); and kouhu means 'Because of what?' or one of the numerous Loglan 'Why?'s'. All the PA words—and there are many hundreds of them—are capable of generating such question words, and with much greater precision than is apparently ever available in the interrogative forms of natural language.
The surprising thing about these interrogatives is their very simple grammar. Like the true-false interrogative ei, they can turn any utterance into a question. The whole utterance is its operand. Thus ei turns Toi tradu ('This is true') into the question Ei toi tradu = 'Is this true?'. Similarly, kouhu turns it into the causal question Kouhu toi tradu = 'Why (because of what cause) is this true?' And three other varieties of 'Why?', namely Moihu Rauhu and Soahu, are available to the loglanist to lend surgical precision to da's inquiries.
Utterance Ordinals. This is the series of compounds formed by attaching the suffix -fi to any NI or TAI word. The results, NefiTofiTefi and finally Rafi, allow the loglanist to number da's utterances—or, for that matter, to number any sequence of clauses or terms within an utterance—with effects like English 'Firstly' 'Secondly' 'Thirdly' and 'Finally' or 'Lastly'. Letter-ordinals may also be employed: AmafiBaifiCaifi and so on; and for the purposes of outlining, the lower-case Latin and the two Greek series of utterance letter-ordinals may also be used: asifi beifi ceifi, Amofi Baofi Caofi and afifi beofi ceofi, etc. These words, too, are grammatical noise.
Salutations. There are four such currently assigned UI words. They are loi ('Hello') loa ('Goodbye') sia ('Thank you') and siu ('You're welcome'). Like the attitudinals the salutations are expressions of the speaker's feelings or desires, but this time, toward da's interlocutor or someone da wishes to speak with. No doubt there will be more such words in time. Their grammar is identical to that of the free modifiers. They may be used anywhere; or, if no special internal emphasis is desired, they are usually placed, like the other UI words, at the head of the utterance: Loi mi bi la Djan = 'Hello! I’m John'.
A Note on Other Free Modifiers. In addition to the UI words, there are three other structures that are handled as free modifiers in Loglan grammar. These are (1) the vocative marker HOI (q.v.) together with any string of one or more name-words that may optionally follow it (Hoi nenkaa = 'Hey, come in! vs. Hoi Djan, nenkaa = 'O John, come in!'); (2) any unmarked string of one or more name-words, that is, unmarked by either LA or HOI (Djan Pol Djonz, nenkaa = 'John Paul Jones, come in!'); and (3) the parenthetic marker KIE together with the parenthesized utterance and the closing parenthesis KIU which will always follow KIE in well-formed speech (Kie Rafi kiu Djan, pa nenkaa = '(Finally) John came in').
These three elements together with Lexeme UI constitute the complete list of free modifiers in Loglan.