on a brute physical fact, whether a piece of paper or only an electronic record. Searle thought that the pervasiveness of social facts could disguise their social construction and ultimate reliance upon the brute fact: thus, we are for example trained from infancy (in his words) to see "cellulose fibres with green and gray stains, or enamel-covered iron concavities containing water...[as] dollar bills, and full bathtubs". Opposition The principle of sufficient reason is sometimes understood to entail that there are no brute facts. Vintiadis In 2018 Elly Vintiadis edited a collection of papers on brute facts that is the first systematic exploration of bruteness and which includes original papers by a number of philosophers and scientists. The collection focuses on physical, emergent and modal brute facts rather than social facts. Vintiadis argues that a properly understood naturalistic attitude requires that we accept the existence of ontological brute facts and also, possibly, emergent brute facts. Beyond the initial definition given above of brute facts as facts that do not have explanations, there is a distinction drawn by Eric Barnes (1994) between epistemically brute facts and ontologically brute facts. The former are for which we do not have an explanation, they are brute for us (e.g., Vintiadis cites the fact that gases behave in a manner described by the Boyle-Charles law was an epistemologically brute fact until its explanation in terms of the kinetic theory of gases). The latter, ontologically brute facts are facts for which there is no explanation in virtue of the way the world is (e.g., the fundamental laws of physics). Which facts we accept as ontologically brute though depends on what kind of theory of explanation we accept (e.g. the properties of fundamental particles will be brute facts under a mereological view of explanation, but a fundamental law will be brute under a covering law model of explanation). Brute necessities John Heil has argued that brute facts can only be contingent facts, since otherwise asking for an explanation for something that couldn't be otherwise doesn't make sense. Joseph Levine agrees with this since for him explanation means removing different possibilities. But not all agree, because some philosophers argue that it is a natural question to ask why some things are necessary. For instance philosopher James Van Cleve believes that brute necessities cannot be excluded. Infinitism According to explanatory infinitism, the chain of explanations goes on infinitely and there