 In spite of the incident, Avempace remained within the Almoravid circle for the rest of his life and for approximately twenty years served as vizier of the mentioned Yahyà ibn Yusuf Ibn Tashfin, another brother of the Sultan ‛Ali Ibn Yusuf Ibn Tashufin in the Maghrib (Maqqari-N: vol.3, p. 28). Vincent Lagardère has done the most extended research on the Almoravids in recent times and provided us with information on all the children of Yusuf Ibn Tashfin (Lagardère 1989: 80 and 174–178). Nevertheless, Lagardère has not found any information on Yahyà other than he was a son of Yusuf and his wife Zaynab, and that he was born around 1084. Thus, he was of a similar age to Avempace.