This article tackles the relationship between causality and determinism, taking the concept of causality as the conceptual foundation that grounded science in the sixteenth and seventeenth centuries. The article examines how the development of causality as a concept has began with the work of Averroes and then picked up by Spinoza during the modern period. In this period, the concept has taken extreme forms of necessity that has turned it into a deterministic principale that frames and guides scientific research. It should also be mentioned that the article proceeds through the premise that Spinoza extended Averroes' philosophical ideas in general and the latter's conception of causality in particular.