I belong to various organizations that have been formulating and posting DEI statements. I am not in favor of posting such a statement because it strikes me as mostly virtue signaling, defined as, "The practice of publicly expressing sentiments intended to demonstrate one's good character or the moral correctness of one's position on a particular issue." (Oxford online dictionary)
My particular concern is when such a statement is put out by a professional organization whose stated purpose is not one of politics or social justice but rather the promotion of better teaching. Members of such organizations typically have expertise in the area of teaching, which qualifies them to promote their own opinions on pedagogical issues and to put out statements about best practices. In contrast, mathematicians and math teachers have no particular expertise on political matters, and they have no more expertise in issues of social justice than does any concerned citizen. Putting forth such statements (e.g., DEI statements) poses a dilemma: either the statements are self-evident, in which case they are pure virtue signaling, or they are propositions on which reasonable people could disagree, in which case they imply a consensus that does not exist. In fact, striving for a political consensus among a nonpartisan professional organization would be antithetical to the goal of diversity.
Here on my personal page, where political opinions reflect no one's beliefs but my own, is some nonpartisan political rhetoric meant to persuade rather than to signal. The following definitions are adapted from sources such as dei.extension.org.
Diversity: the presence of differences including those of race, gender, etc.
Equity: as it relates to math education, it means either (1) equal opportunity for educational achievement in a given setting, or (2) equal educational outcomes across groups; whether (1) or (2) is more what is meant depends on whom you ask and in what context.
Inclusion: ensuring that all participants feel welcomed (this is aimed especially at previously marginalized groups).
I am very much pro-inclusion. On the issue of equity, I see a mix of pros and cons. I find diversity largely to be a non-issue as it relates to math teaching. Here are some details as to why.
INCLUSION is one of the fundamental things that teachers strive for when aiming to improve their classrooms: they seek ways to engage students who appear not to be engaged. Insofar as these students skew toward marginalized groups, general efforts at inclusion will also skew toward these groups. Regardless, I support inclusive practices and I think they are an obvious correlate of good teaching.
EQUITY in the second sense (equal outcomes) isn't anywhere close to attainable right now. One might consider it a laudable long-term goal; however, efforts aimed directly at equalizing outcomes are likely to backfire. EQUITY in the first sense (equal opportunity for value added) is a proposition on which reasonable people could disagree. Some might argue that public schooling is by its nature aimed at the modal student, and that outliers such as gifted or struggling students cannot expect lessons to be aimed at them as much as they are aimed at the average student. Others might argue that gifted students represent a potentially large societal payoff (rocket scientists, etc.) and that more effort, rather than less, should be spent to teach them. Still others could argue that the weakest students deserve disproportionate efforts because they have the greatest need. These are important questions of policy and ethics, but mathematicians and teachers don't have any special claim on the right view here, and personally, I'm on the fence.
DIVERSITY seems to me more to be a description than a goal. Our population is diverse. That's a fact. We can celebrate it. We can recognize that diversity of mathematical backgrounds makes teaching math a lot more difficult. The goal in most classrooms is not increasing diversity but dealing with it. The other kind of diversity that DEI statements aim at is diversity of exemplars: cultural details appearing in word problems, bits of math history, and the diversity of the teachers themselves. As teachers, we can’t change our own demographics, so there’s not much point in my having a position on my contribution to diversity through personal example. About exemplars in our lessons, it is true that we occasionally get to make these choices in our classrooms, though cultural references appear much less frequently in math classrooms than in, say, history or English classrooms. We can, and arguably should, dress up our examples with signposts of diversity. However, for those seeking to help at-risk populations, there are much more effective things we can do.
Improving classroom strategies, teacher training, curricula and assessments, all of which are done by groups such as TPSE that I am involved with, have immeasurably greater effect on marginalized groups (and indeed on all students) than do DEI efforts in the classroom. Here, at least, I do speak with some expertise. I don't think there is much justification for DEI efforts to be mounted front and center on the websites of math education groups I belong to. These solidarity statements, as they become increasingly obligatory, lose meaning and, to me, detract from an otherwise worthy mission.