This review analyses Ali Paya’s work on Islam and modernity through the lens of critical rationalism, an epistemological approach that treats knowledge as conjectural and subject to continuous critique. It outlines Paya’s attempt to engage Islamic thought with modern philosophical challenges, including questions of epistemic certainty, the relationship between religion and science, and the possibility of Islamising knowledge. The review highlights key tensions in Paya’s framework, particularly his rejection of justificationism and his redefinition of certainty, while questioning whether such positions can be consistently maintained. It also discusses his reinterpretation of the role of jurists and his analysis of religious violence. The review concludes by acknowledging the importance of Paya’s emphasis on intellectual humility and critical engagement, while noting unresolved philosophical issues in his approach.