Possibility (Möglichkeit): as an existential, it is the most original and positive ontological determination of Dasein, 143-144; higher than actuality, 38, 262, 299; of Dasein, 7, 12-13, 19-20, 42-43, 50, 62, 104, 125-126, 144, 148, 170, 173, 177-178, 181, 187-188, 191, 193-195, 199, 211, 236, 239-240, 244, 250, 260, 264, 266, 270, 273, 284, 288, 295, 325, 384, 394, 396; of impossibiiity of existence, 250, 262, 265-266, 306; impossible and possible, 342; death as, 248, 250-266, 302-303, 307, 309, 391; being toward, 262; extreme 122, 182; existentiell, 267-270 (§ 54), 336-337; factical, 264, 299, 383-384; ontic and ontological, 312; category of logical, 143; as project of understanding, 145-148, 151, 194, 260, 270, 274, 284-285, 295, 302, 306, 312, 324, 336, 339, 383, 387, 394, 397. See also condition of possibility; future; meaning; potentiality of being; project (BT)