http://www.special-dictionary.com/latin/e/ens_a_se.htm
a being in itself
https://mymemory.translated.net/en/Latin/English/ens-a-se
by being herself
https://www.catholicculture.org/culture/library/dictionary/index.cfm?id=33330
Being. In philosophy ens is the common denominator of all reality, and is variously classified according to the different kinds of reality known to the human mind. Thus ens a se is being from itself, or the uncaused Being who is God; ens ab alio is being from another, namely produced or caused being or creature; ens in se is being in itself, and also ens per se which is being through its own nature or being in an unqualified sense, and in both cases is substance; ens entis is being of being, which means that it cannot have existence in itself but only in a substance, hence an accident; ens rationis is a "being" or creation of reason hence a purely logical or conceptual being or idea of something that does not really exist outside the mind; and ens ut sic is being as such, apart from its manifold and varied forms of existence, and is the object of metaphysics or the philosophy of being. (Etym. Latin ens being, a being, something having existence.)
Roughly speaking, it was during the first three decades of this century that the foundation of contemporary European philosophy were laid by three German thinkers: Husserl (phenomenology), Scheler (Philosophy of Man), and Heidegger (Ontology of Dasein).
But throughout all these studies his philosophy is directed towards two major objectives: the determination of man's place in nature and the determination of the ens a se (as primordial source of being) in both philosophy and religion. (Manfred Frings, 1996, p. 1)
