Abstract: It is well known that cognitive stages can be improved by education. In the light of this knowledge, the purpose of this study was to understand whether education philosophies have an effect on cognitive stages development. To achieve this purpose, two design based disciplines which have been rooted different philosophical perspectives were designated to collect data. The first one is Department of Architecture, represents constructivist education philosophy and the second one is Department of Mechanical Engineering represents traditional education philosophy. A sample of 42 students, whom enrolled first and last grades of the departments, voluntarily participated in the study. Participants were asked to answer Social Paradigm Belief Inventory (SPBI) to determine their cognitive stages, and by the comparison of results according to grades and disciplines, it is found that there is a slight, yet significant difference between the cognitive developments of students, favour to Department of Architecture. So, it is concluded that educational philosophies might have effect on cognitive development on behalf of constructivist education philosophy.