Hadith of Golden Chain al-Bayt, hence called "Hadith of Golden Chain". Several Important hadith collections quoted it as "Al-Tawhid", "Ma'ani al-Akhbar", and Oyoun Akhbar Al-Ridha of al-Shaykh al-Saduq and Al-Amali of Shaykh Tusi. The hadith is also narrated in sunni hadith books. Regarding the implications of the hadith, there are two extreme opinions by Sunni scholars; While some of them discrediting the hadith by implying that the Sunni books lack it, some others claim that all Sunni scholars accepted it. According to shia, two important points may be derived from the Hadith. On one hand, monotheism takes the believers to "Allah's fortress", which is
Genus–differentia definition Genus–differentia definition A genus–differentia definition is a type of intensional definition, and it is composed of two parts: For example, consider these two definitions: Those definitions can be expressed as one genus and two "differentiae": The process of producing new definitions by "extending" existing definitions is commonly known as differentiation (and also as derivation). The reverse process, by which just part of an existing definition is used itself as a new definition, is called abstraction; the new definition is called "an abstraction" and it is said to have been "abstracted away from" the existing definition. For instance, consider the following: