<p>This study constitutes a serious attempt to reshape the epistemological framework for understanding unexpected phenomena in organic chemistry, through a thorough critical analysis of fifteen historically documented cases spanning two centuries of chemical development. The study moves from the traditional model that treats “chance” as accidental luck, to the “material response” model that views these phenomena as manifestations of the intrinsic complexity of matter and its capacity to surprise prevailing theoretical models. This transformation necessitates rethinking fundamental concepts in chemical philosophy. The methodology relies on a precise analytical trilogy comprising critical historical reading of knowledge contexts, philosophical induction of epistemological patterns, and the study of socio-institutional dynamics governing the acceptance or rejection of anomalous phenomena. The integrated application of this methodology reveals new dimensions in understanding chemical discovery. The study concludes that unexpected phenomena represent fertile epistemological moments revealing the dialectical dialogue between abstract reason and material complexity, and proposes a radical shift in understanding the nature of chemical knowledge and its production methods, opening new horizons for future research in the philosophy of chemistry. The analysis distinguishes between serendipity, unexpectedness, and opportunistic observation, drawing on relevant literature to contextualize these concepts.</p>