In popular cultures, "Extraterrestrials" are life forms — especially intelligent life forms— that are of extraterrestrial origin (often also called "aliens").
Famous quotes containing the words life and/or culture:
“The life of man is of no greater importance to the universe than that of an oyster.”
—David Hume (1711–1776)
“Insolent youth rides, now, in the whirlwind. For those modern iconoclasts who are without culture possess, apparently, all the courage.”
—Ellen Glasgow (1873–1945)