Lingua philosophica ("the philosophical language") is a very early constructed language invented by George Dalgarno (c. 1626-1687), a Scottish schoolteacher, published by him in his Ars Signorum ("Art of Signs"), a lengthy essay published in 1661 which both attempted to set out the philosophical basis of language, as Dalgarno perceived it, and to sketch (in some detail) a constructed language that would, ideally, represent each idea by a word, related ideas by related words, and be sufficiently rational to train its learners' minds in philosophical rigor.
Whether or not Dalgarno succeeded at this task, his Lingua Philosophica is one of the earliest fully functional constructed languages, and most likely the earliest in Europe.
It consists of:
- A lengthy list of roots corresponding to what Dalgarno believed to be basic linguistic concepts or ideas.
- A much briefer grammatical apparatus (chiefly verbal and adjectival inflexional suffixes) which could be used with these roots.
- A "Lexicon" of 1370 Latin words glossed in Lingua Philosophica, often by compounding existing roots
- A set of writings, primarily translations, in Lingua Philosophica. These include:
- A foreword addressed to King Charles II.
- The Lord's Prayer in Lingua Philosophica.
- A translation of the first chapter of Genesis.
- Translations of the first five Psalms.
- Translations of two short Fables of Æsop.
These texts are broadly consistent with each other and with the lexicon, but there are some differences and inconsistencies, likely due to their being composed at different stages of invention or revision of the language and not later edited to be more consistent with each other.
There are also several example sentences given in the main body of the Ars Signorum.
i, e, η, a, o, υ, u These perhaps represent the sounds /i/ /e/ /ɛ/ /a/ /ɔ/ /o/ /u/, if Dalgarno's intent (somewhat obscurely expressed) was a symmetrical 7-vowel system. Their actual pronunciation, considering Dalgarno's probable native phonology, may have been closer to /i~ɪ/, /e/, /ɛ/, /æ~a/, /ɒ/, /ɔ~ʊ/, /u/.
As it is difficult to distinguish υ and u at a glance, ʊ will be substituted for υ hereafter.
Diphthongs: ai, ei, oi
- Represented by the letter f. It is unclear whether it was actually intended to be pronounced [f]; it was, however, intended to fill the slot of a velar nasal.
- See ŋ above
The sound [ʃ] is also found; however, this is not truly a phoneme, but represents underlying /sr/.
As an artificial language with no internal history and no intent of mimicking a natural language, there is little in the way of phonology in Lingua Philosophica; by and large, underlying and surface realizations are identical. Nonetheless, there are a few "phonological rules":
- The vowel /i/ is inserted between a morpheme ending in a consonant and a following morpheme beginning with a vowel.
- The vowel /i/ is inserted following a double consonant at the end of a word.
- The consonant /s/ is inserted between a morpheme ending in a vowel and a following morpheme beginning with a vowel.
The morphology of Lingua Philosophica is largely concatenative, consisting of the addition of suffixes (and some prefixes). Nonetheless, there are some exceptions:
Roots for the most part take the form (C)(C)VC. They may be primary or secondary (derived from primary). Primary roots can begin with any consonant except /r/, /l/, or [ʃ]. They can also begin with the clusters /sp/, /st/, /sk/.
Secondary roots are formed for the most part by adding the segments /r/ or /l/ to a primary root. The /r/ is used to indicate a meaning in some way 'opposite' to that of the primary root; the /l/ indicates a mean between the primary root and the r-root.
- If a root begins with a vowel, the /r/ or /l/ becomes the initial consonant, e.g is "sea," ris "river."
- If a root ends with a vowel, the /r/ or /l/ becomes the final consonant, e.g. fa "breast," far "back."
- If the root begins with a consonant or consonant cluster, the /r/ or /l/ follows as the last consonant before the vowel, e.g. gomu "light," gromu "darkness."
- If the root begins with /s/ and /r/ is inserted after it, the cluster /sr/ becomes [ʃ]: e.g. sim good, shim bad.
The plurals of nouns and pronouns are formed by doubling a final consonant and adding i — which, by the intent of the creator, is solely a supporting vowel. as "star," pl. assi "stars" nim "water," pl. nimmi "waters" kanel "king," pl. kanelli "kings" lal "I," pl. lalli "we"
If the word is a polysyllable ending with a vowel, only the last consonant is doubled, without the addition of i: gomu "light," pl. gommu "lights"
If the word is a monosyllable ending with a vowel, the consonant s is added before i, and is doubled: fʊ "buttock," pl. fʊssi "buttocks."
Verbs are the most elaborately inflected word forms in Lingua Philosophica. They consist of a root followed by up to three slots:
Slot 1 contains the suffix -r or zero. The suffix -r forms denominal, deadjectival, or causative verbs, more or less following the various senses of English "make":
- rag "fruit," ragr- "make fruit, produce fruit"
- pem "know," pemr- "make known, declare"
- skam "holy," skamr- "make holy"
- pon "love," ponr- "cause to love"
Slot 2 contains either the active suffix -e or the passive suffix -o. If no further suffix follows, these are the present active and past passive participles, respectively.
-o can also be used, like English -ed, to indicate the permanent possession or endowment with a thing:
- spi "wing," spiso "winged, having wings"
Slot 3 contains tense and mood endings:
- -ʊ infinitive
- -i present
- -u future
- -a perfect
- -o imperative