The problem that will be dealt with in this paper is al-Ghazālī’s account of causality in the observed phenomenal world where he denies the necessity of that causation. This denial brought about Ibn Rushd’s accusation on the denial of knowledge, arguing that knowledge is based on causality in the phenomenal words. However, detailed perusal of al-Ghazālī’s works suggests that Ibn Rushd’s accusation is not the case. al-Ghazālī differentiates between knowledge of the fact and knowledge of reasoned fact, or in other words he distinguished ontological causality from logical causality. In addition, al-Ghazālī’s denial of causal necessity is supported by his own logic, where the knowledge attainment becomes possible when it is examined from demonstrative sciences, especially from empirically tested premises (almujarrabāt)