The first quarto's version of the speech of William Shakespeare’s famous Hamlet quote: “To be or not to be, I there’s the point, to die, to sleep, is that all?” which amounts to a frank and straightforward query about the point of existence, and seems to exemplify what most modern people associate with the term "being". [4]

The term being refers to the quality or state of having existence (e.g. human existence). [1] In particular, the term being is often associated with “conscious existence”, life, or the qualities that constitute the essence of a living thing. [2] The term is often found in conjunction with the word human, as in “human being”, implying both the anatomical, physiological, and psychological structure, but also whatever may constitute the essence of the individual.

To be or not to be
English author William Shakespeare's famous "to be or not to be" query seems to well-capture the gist of the modern person's notion of being, in the sense of a term captures or embodies one's theory of existence. Russian-born Israeli chemical engineer Alec Groysman comments on this logic thermodynamically in his 2004 article “Aesthetic, Philosophical and Historical aspects in the Physical Chemistry education”, where he states: [2]

“The relationship of probability and entropy (more precisely, the decision about spontaneous occurrence of process) or calculation of Gibbs energy for some chemical reactions, is similar to Hamlet’s ‘to be or not to be?’ of William Shakespeare.”

which seems cogent, being that Gibbs free energy, according to Erwin Schrodinger (What is Life?, 1944), is the subject one is supposed to turn to if one is to understand, supposedly, what life is in terms of chemistry and physics.

Activation and being
In a short essay titled ‘Action and Activation’, French philosopher Pierre Teilhard gives an excellent definition of life in relation to being. In particular, being, in metaphysics, Teilhard states “can be defined with a precision that is geometric in type”; energy, however, presents itself to the physicist as a magnitude that is still open to all sorts of possible corrections or improvements.” In relation to the combined mechanism of activation, being, and energy, Teilhard reasons that: [3]

“One of the most distinctive characteristics of living substance in action is undoubtedly the predominate importance assumed in it by the fact of being (or of not being) appropriately responsive to a stimulus and stimulated.”

Here we see Teilhard attempting to frame out the concept of "being" in a pure physical-chemical perspective.

See also
● Human molecule
● Human particle
● Animate being
● Inanimate being
● Living being
● Material being
● Chemical being
● Physical being

References
1. Being (noun) – Merriam-Webster Collegiate Dictionary, 2000, CD-ROM, version 2.5.
2. Being (noun) – Random House Unabridged Dictionary, © Random House, Inc. 2006.
3. Teilhard, Pierre. (1953). “The Energy of Evolution” in Activation of Energy, chapter: “Activation of Energy (section II: Action and Activation, or, On the Dynamic Role of Foresight in the New Evolution)”. Unpublished, New York, May 24. (Oeuvres, VII).
4. To be, or not to be – Wikipedia.
5. Groysman, Alec. (2004). “Aesthetic, Philosophical and Historical aspects in the Physical Chemistry education”, in: Trends in Electrochemistry and Corrosion at the Beginning of the 21st Century (pgs. 1203-1226). Edicions Universitat Barcelona.