“I shall likewise mention those (narrators) who came after them, giving additional information about them. I do this so that it can be clarified whose transmission (of traditions) is praised and whose information is transmitted, whose transmission is to be rejected and whose transmission is to be disregarded…The reader should know that with respect to all I have mentioned and made it a condition to set down in this book of mine, I rely upon traditions and reports which have been transmitted and which I attribute to their transmitters. I rely only very rarely upon (my own) rationality and internal thought processes. For no knowledge of the history of men of the past and of recent men and events is attainable by those who were not able to observe them and did not live in their time, except through information and transmission produced by informants and transmitters. This knowledge cannot be brought out by reason or produced by internal thought processes. This book of mine may contain some information mentioned by me on the authority of certain men of the past, which the reader may disapprove of and the listener may find detestable, because he can find nothing sound and no real meaning in it. In such cases, he should know that it is not my fault that such information comes to him, but the fault of someone who transmitted it to me. I HAVE MERELY REPORTED IT as it was reported to me.(Tareekh at-Tabari, Vol.1, Introduction