 The Instituto de Investigaciones Filosóficas is where Luis Villoro (1922–2014) spent the bulk of his academic career. Born in Barcelona (Spain) to a Mexican mother and a Spanish father, and raised in Spain and Belgium, he settled in Mexico at the outbreak of the Second World War and became a Mexican citizen. He did his undergraduate and graduate studies at the Universidad Autónoma de México and spent research periods in France and Germany. In 1982, he published the first analytically oriented book on epistemology written in Spanish: Creer, saber, conocer (Villoro 1982), translated into English as Belief, Personal, and Propositional Knowledge (Villoro 1998). Villoro examined fundamental concepts such as belief, knowledge, truth, objectivity, and epistemic communities. He distinguished between saber and conocer, which roughly correspond to what may be called “propositional” and “personal knowledge”, respectively, the latter consisting in having direct experiences of a given object. S can assert that he has personal knowledge of x provided that he has the relevant personal experiences, but if S wants to justify to someone else the claim that he has such knowledge of x, S must show that he has propositional knowledge of his personal knowledge. Villoro seems to have defended a form of epistemic relativism inasmuch as he claimed that to know (in the sense of saber) that p is to believe that p, and to have objectively sufficient reasons to so believe—an objectively sufficient reason being one that is conclusive, coherent, and complete—but also maintained that what is considered as an objectively sufficient reason in one epistemic community may not be so considered in another. For this reason, he claimed that empirical knowledge is fallible: on the basis of the reasons that are objectively sufficient for any member of his epistemic community, S knows that p, but he cannot rule out the possibility that there might be contrary reasons available to a different epistemic community that would undermine his knowledge that p. Objectively sufficient reasons are our best guarantee of empirical truths, but they do not of necessity imply such truths (Villoro 1982: 180, 192). Villoro held that the view that all knowledge is socially conditioned is the only valid alternative to skepticism (1982: 164). He also proposed a surprising reform of the traditional concept of knowledge: the notion of truth should not be included in the definition of knowledge because, even though the notion of an objectively sufficient reason cannot be understood without the notion of truth, one may know that p even if p is not true, for truth is not a necessary condition for a reason to be objectively sufficient (1982: ch. 8). (For a fuller overview of Villoro’s book, see Cresto 2010a: 474–477.)