This question (what is the philosophy of mathematics education?) provokes a number of reactions, even before one tries to answer it. Is it a philosophy of mathematics education, or is it the philosophy of mathematics education? Use of the preposition ‘a’ suggests that what is being offered is one of several such perspectives, practices or areas of study. Use of the definite article ‘the’ suggests to some the arrogation of definitiveness to the account given.[1] In other words, it is the dominant or otherwise unique account of philosophy of mathematics education. However, an alternative reading is that ‘the’ refers to a definite area of enquiry, a specific domain, within which one account is offered. So the philosophy of mathematics education need not be a dominant interpretation so much as an area of study, an area of investigation, and hence something with this title can be an exploratory assay into this area. This is what I intend here.