h₁es-

The root *h₁es- ("to be") occupies a foundational position in PIE reconstruction, as the existential and copular verb is among the most frequently used lexical items in any language. The suppletive paradigm of "to be" in many daughter languages—English be/is/was, for instance—reflects distinct PIE roots that were combined in prehistoric times. Latin esse ("to be") continues the root directly, with the present indicative sum (from *h₁es-mi, "I am") showing regular loss of the laryngeal. The participial form ēns ("being") underlies entity, essence (essentia, a Ciceronian coinage), and absence (absēns, "being away"). The philosophical vocabulary of medieval and modern European thought is built substantially on derivatives of this root. Greek eimí (εἰμί, "I am") preserves the first-person singular with an ending that differs from the Latin but derives from the same PIE form *h₁és-mi. The third-person singular estí (ἐστί) matches Sanskrit ásti and Latin est with exact phonological regularity. The philosophical term ontology derives from the present participle ōn (ὤν, "being"). Sanskrit ásti ("is") continues the third-person singular directly. The present participle sánt- ("being, existing") yields the concept of sat ("truth, existence") fundamental to Indian philosophy, as in satya ("truth") and the compound sat-chit-ananda. The Germanic reflexes are limited to the third-person forms: English is (from *h₁és-ti via Proto-Germanic *isti), German ist, and Gothic ist. The remaining paradigm in Germanic is supplied by other roots (*bʰuH- giving be/been and *h₂wes- giving was/were). Old Church Slavonic jestŭ ("is"), Lithuanian ẽsti, Old Irish is, and Armenian ē all continue the root. The Hittite form ēšzi ("is") provides crucial evidence from the Anatolian branch, the earliest attested Indo-European language family. The laryngeal *h₁ is reconstructed on the basis of its non-colouring effect: the root vowel *e remains unchanged in daughter languages, unlike *h₂ (which produces *a-colouring) or *h₃ (which produces *o-colouring). This distributional evidence is central to the modern reconstruction of the PIE laryngeal system.