Chemistry deserves more philosophical attention not so much to do justice to a long-neglected science or to enhance its cultural prestige, but to undermine a number of taken-for-granted assumptions about scientific rationality and more importantly to diversify our metaphysical views of nature and reality. In brief, this paper does not make the case for a philosophy of chemistry. It rather urges philosophers of science to listen to chemists and discuss what they learn from them. Because over the course of many centuries chemists have developed a special access to nature and a special way of investigating and dealing with material substances, they have confronted a number of epistemological and ontological issues that are worth discussing. Following critical remarks about the disciplinary... partition of philosophy, a historical section presents the contributions to philosophy of a few French twentieth-century chemists-turned philosophers to emphasize how they have challenged the dominant philosophical categories. The final section develops one of the lessons that philosophers can learn from chemists: to pay attention to things, to their materiality and activity in order to develop new ontological perspectives.