In the psychology of perception, there’s the idea of a just-noticeable difference (JND) in some stimulus. For example, if a person is looking at a light, a JND is the smallest change in light that they’ll notice.
Some of the discussion around the changes that were just made in the temple ceremonies has made me think that we could define a parallel idea for how meaningful a change is: a just-meaningful difference (JMD). A JMD would be a change in something that’s just small enough to be meaningful.

To me, the changes the Church just made are far, far beyond the JMD threshold. The fact that women’s and men’s covenants are now parallel to each other rather than having women covenant to hearken to their husbands and men covenant to obey God is, I think, huge. The hearken covenant (and its even harsher predecessor, the obey covenant) have been the source of so much pain to so many Mormon women over the years. Similarly, the changes that have Eve no longer be silenced for the latter part of the endowment, and dropping the requirement that women be veiled are also very big. All these changes signal a fundamental reorganization of how women and men are though of being in relation to God. Instead of a hierarchical view where God presides over men, and men preside over women–one that Paul and Brigham Young would have preferred–we’ve taken some steps toward one where God is over all, regardless of their gender.
Read More