Abstract
Avicenna and Al-Ghazali are two Islamic philosophers, who wrote on Islamic philosophy, and were among the most prolific philosophers in philosophy. It can be said that the philosopher is a human being like others, and he is the son of his time in which he is born, and intellectual, political and social events effect of his personality. Therefore, he is known by simply studying the prevailing social pattern of his time.
Avicenna was a lover of science and scholars and had knowledge of the methods of literature and philosophy, held the ministry and has many books.
For Al-Ghazali, philosophy in his time became public, due to the spread of doctrines and their opposition, and the ideas of Al-Ghazali represented the response to and discussion of philosophers, correcting what required correction, and evaluating what deserved evaluation.
Avicenna and Al-Ghazali have authored many books, but what concerns us in this research is a comparison between the natural terms contained in Ibn Sina's Risalat al-Hudud and the Risala al-Hudud by al-Ghazali.