sentences: if something does not contain something else, then that something else cannot be found in that something
docs: thing is substance. something_that is ours_belongs_to_us. separated_thing is divided_thing. else is river. person is individual_unlike_other. no_thing is nothing_yet_no_one_knows. non_fluidlike_substance is tangible_thing. nothing_here is like. people_do_not_know_if_there is god. otherness is difference.