Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class I. Words Expressing Abstract Relations
Section I. Existence
1. Being, in the Abstract

1. Existence.

   NOUN:EXISTENCE, being, entity, ens [L.], esse [L.], subsistence; quid, hypaxis [rare], automaton.
  REALITY, actuality; positiveness &c. adj.; fact, matter of fact, sober reality; truth [See Truth]; actual existence.
  PRESENCE (existence in space) [See Presence]; coexistence [See Synchronism].
  STUBBORN FACT; not a dream [See Imagination]; no joke.
  ESSENCE, inmost nature, center of life, inner reality, vital principle.
   VERB:EXIST, be; have being &c. n.; subsist, live, breathe, stand, obtain, be the case; occur (event) [See Eventuality]; have place, rank, prevail; find oneself, pass the time, vegetate.
  come into existence &c. n.; arise (begin) [See Beginning]; come forth (appear) [See Visibility].
  BECOME (be converted) [See Conversion]; bring into existence [See Production]; coexist, postexist [rare], preëxist [rare].
  CONSIST IN, lie in; be comprised in, be contained in, be constituted by.
  ABIDE, continue, endure, last, remain.
   ADJECTIVE:EXISTING &c. v.; existent, subsistent, under the sun; in existence &c. n.; extant; afloat, on foot, current, prevalent; undestroyed.
  REAL, actual, positive, absolute; factual, veritable, true [See Truth]; substantial, substantive; self-existing, self-existent; essential, beënt.
  WELL-FOUNDED, well-grounded; unideal, unimagined; not potential [See Nonexistence]; authentic.
   ADVERB:ACTUALLY &c. adj.; in fact, in point of fact, in reality; indeed; de facto [L.], ipso facto [L.].
  1. Ens rationi.
  2. cogito ergo sum.
  3. Think’st thou existence doth depend on time?—Byron
  4. All is concenter’d in a life intense.—Byron
  5. To live is not merely to breathe, it is to act.—Rousseau
  6. The mainspring of life is in the heart.—Amiel
  7. I came like Water, and like Wind I go.—Omar Khayyám—Fitzgerald