HAD'ITH (Ar. hadith, tradition, from hadatha, to occur). The general designation in Arabic for a story or tradition, but more specifically applied to the traditions about Mohammed, the prophet's sayings and doings, which, as a complement to the Koran, form, together with it, the supreme authority for all religious and legal questions of the Mohammedans. Originally the traditions were transmitted orally; but the danger of their being entirely forgotten gradually led to their being written down in the first centuries after Mohammed. The earlier collections, however, possess only individual authority, and make no claim to systematic arrangement or comprehensiveness. Such collections are known as musnads, ‘genealogical chains,’ from the fact that each tradition is traced back to its ultimate authoritative source. Eight of such musnad collections are known to us, though many more were produced. The higher class of Hadith literature, however, is represented by collections termed musannat, ‘systematized,’ in which the traditions are divided according to subjects and treated with reference to their ritualistic, historical, and ethical import. The attempt is made to carry each utterance of the prophet back from one source to the other, until a contemporary of Mohammed is reached, and if the chain is complete the tradition is considered to be of the first class; the value of the defective traditions varies again according to the number of links missing, and the names of those who have transmitted the traditions. It will be seen that in this way the door is opened for almost endless variety of opinions as to the exact value of this or that tradition. The principal and most authoritative collections of traditions are those of Bokhari, Moslim, Abu Daud, Tirmidi, Nasa'i, and Maja. Of these again, which were all produced in the ninth century, the most important code is the Sahih of Bokhari (810-870), who, it is said, spent sixteen years of his life in traveling through the length and breadth of the land for the purpose of collecting such traditions, and who singled out, from a number of 60,000, about 7270, as alone genuine. Besides numerous editions published within the last fifty years in the Orient, a standard European edition of the Sahih was published by the later Professor Krehl, Le recueil des traditions musulmanes, par . . . al-Bokhari (Leyden, 1862-68). The six authoritative Hadith collections are far from exhausting the Hadith literature. Every generation, almost, produced collections of traditions aiming to fill out gaps or to determine the value of traditions. In this way an enormous Hadith literature grew up which is fully discussed by Goldziher, in his Mohammedanische Studien, vol. ii. (Halle, 1890). See Sunna; Mohammedanism; Koran.