We say that everything either is always and of necessity (necessity not in the sense of violence, but that which we appeal to in demonstrations), or is for the most part, or is neither for the most part, nor always and of necessity, but merely as it chances; e.g.
Gauza oro, edo beti eta nahitaez da (ez indarrez hartutako nahitaezkoa, demostrazioetan erabiltzen dugun hori baizik), 35) edo gehienetan, edo ez gehienetan, ezta beti eta nahitaez ere, halabeharrez baizik;