In recent years, there has been much concern expressed about the underrepresentation of women in academic philosophy. A full explanation of this troubling phenomenon is likely to be quite complex since there are, almost certainly, many factors that contribute to the gender disparity. Our goal in this paper is to call attention to a cluster of phenomena that may be contributing to the underrepresentation of women in philosophy, though until now these phenomena have been largely invisible. The findings we review indicate that when women and men with little or no philosophical training are presented with standard philosophical thought experiments, in many cases their intuitions about these cases are significantly different. We suspect that these differences could be playing an important role in shaping the demography of the profession. But at present this is only an hypothesis, since we have no evidence that bears directly on the causal relation between the gender gap in academic philosophy and the facts about intuition that we will recount. In future work, we plan to focus on that causal link. However, we believe that the facts we report about gender differences in philosophical intuitions are both important and disturbing, and that philosophers (and others) should begin thinking about their implications both for philosophical pedagogy and for the methods that philosophers standardly use to support their theories. It is our hope that this paper will help to launch conversations on these issues both within the philosophical community and beyond.Here is how we plan to proceed. In section 1 we briefly review some of the data on the underrepresentation of women in academic philosophy. In section 2 we explain how we use the term 'intuition', and offer a brief account of how intuitions are invoked in philosophical argument and philosophical theory building. The third section is the longest and most important. It is in that section that we set out the evidence for gender differences in philosophical intuition. We also mention some evidence about gender differences in decisions and behaviors that are (or at least should be) of considerable interest to philosophers. In the fourth section, our focus switches from facts to hypotheses. In this section we explain how differences in philosophical 1 We are very grateful to