Let's just say, about Being, and about Being in the World, and Being in Time (with a nod to George Pattison):

Twaddle.  There is no proof that the Being which you think so big a deal--however you qualify it--is anything but an elementary, and perfectly silly, mistaking of linguistic peculiarities and oddities of grammar for material (In-the-Universe) realities.  Like, for example, "God."  And that's really all (except for the obscure pleasure you take in mystifying yourself) there is to it. . . Apart from the pernicious habit that you seem to have acquired from St. Thomas Aquinas of making a predicate of existence.