Abstract
Today, one of the methods of getting out of the ambiguities left in the history of the past is to compare similar works and find the reasons for those differences. Finding the causes of these effects has always opened new windows of science. That is why Khaleghi Motlaq, after spending more than thirty years comparing fifty-five different manuscript works of the Shahnameh, confirms the superiority of ten of them over the rest (cf. Khaleghi Motlaq, Vol. 1, 2015: 92); and here, by putting together the similarities, differences, and a brief digression into their causality with the help of Geiger's theories, we are trying to categorize and put them together in such a way that the reader can extract the necessary points by reading them. 1 Similarities that result from the same content and differences that result from the author's specific style, the historical period of each author's life, and different sources. In these comparisons, we can point out the power of precise writing and giving detail to seemingly short contents, or from another perspective, perhaps we can understand the existence of greater sources. In the history of Tha'alabi, with an approximate similarity to the Khodai-namehs, including the Shahnameh, the beginning of creation means; He describes and describes Kiyomars and continues until the end - Yazdgerd III and the beginning of the Arab invasion. This approach, which is not unlike the Shahnameh, is written in the prose style of Mursal and with a religious approach. All three works have their own capabilities that can be criticized and examined individually or in pairs. Certainly, comparing all three of them together and creating a comparison triangle will extract useful and beautiful points; because the more branches the comparison has, the more diverse the outputs will be.