Deism from the beginning has positioned itself as a heterodox religious identity contrary to orthodoxy. In this regard, it is the review of established classical theological presuppositions regarding the following headings: conception of God; God-world relationship; religion-science relationship; ethical considerations regarding the problem of evil, etc. In these contexts, deism could be seen as a sort of religious self-criticism. As arose in British philosophical-theological circles, deism sounds to have resisted some conventional Christian presuppositions as put forward by E. Herbert of Cherbury, the father of English deism, in the forthcoming articles: “There is a supreme God. This sovereign deity should be worshipped. Virtue arises from the piety created by this worship. As the man is filled with wickedness, he needs repentance, which means communication with this sovereign Being. There is reward or punishment in the life to come.” In the course of time, different kinds of deisms turned up, ranging from accepting God as a sublime creator alone and rejecting revelation, i.e., institutional religion, to those accepting religion on the condition that it should be compatible with reason. Samuel Clarke mentions the arguments of different kinds of deists and skillfully criticizes them. Historical and contemporary deism have the following in common: “The compromise between truth of revelation and truth of reason; saving knowledge versus saving faith; rejection of institutional structures; glorification of reason and human nature; ethical rationality.” With this doctrinal backdrop, hot debates on deism in Turkey have recently gotten new dimensions. Figures showing the rise of deism in recent years under an Islamist political rule makes the case all the more thought-provoking. The visibility of religion in the public sphere has increased, and the rate of religiosity would also be expected to increase. However, the result is quite the opposite. There is a widespread and remarkable secularization in conservative circles. After they got the political power and economic welfare, which enabled them to attain worldly glory, they have gradually left religious glory behind and glorified profanity. In this case, deism seems to take the form of secularized orthodoxy. Deists in Turkey, rather than rejecting revealed religion they want it to be compatible with reason, to demythologize it from supernatural narratives, and to find a way of getting rid of fanatical elements in the religion. They want to replace religious institutional authority with the authority of reason, which rests itself on innate ideas and a priori truths. They claim ethical rationality, which means ethical truths are accessible through reasoning. My study tackles some statistical data specifically signifying why youngsters tend to claim to be deists. Some surveys among high school students have been included in the study and due evaluations have been made. It seems sectarian identities, radical voices, authoritative religious language, blockades to freedom of speech, a dichotomy between religious and scientific facts in the curricula and mythological religious language are among the reasons counted by the youngster to reject conventional religion and embrace deism. The mainstream theological tradition of Islam is quite familiar with deistic claims. The discussions on deism will finally bring the enlightened minds together with the reasonable religious line.