Section 2A/6 of the Mencius tells us that the heart of deference (辭讓) is the starting point of ritual. I’ll try to convince you that this is a puzzling claim, and then suggest a solution to the puzzle.
The puzzle is that ritual obviously mobilises motives other than deference, and calls for behaviour that is not simply deferential. Think of the way that grief takes on ritualised shape in funerals: this is not just an extension of deference. So, why did it make sense to the author or authors of Mencius 2A/6 to say that deference is the starting-point of ritual?
You could solve this puzzle if you thought that extending the heart of deference could give it a radically different character, so that (for example) the sort of grief appropriate during a funeral could count as an extension of deference. I don’t think anyone reads Mencius 2A/6 this way, however, and if it were right, why are there four hearts rather than just one that can be extended in arbitrary ways?
You could also deny that the Mencians were trying to give a full account of the psychology of ritual here, and that they would agree we need more than just deference to participate correctly in ritual. Perhaps you’d mention that the parallel passage in Mencius 6A/6 mentions a heart of respect or reverence rather than of deference as evidence that they recognised that ritual had a more complex psychological basis. Maybe in each of these passages it was for literary reasons alone that they chose just one motive to be characteristic of ritual, and the choices were not meant to carry philosophical weight.
Still, the derivation of benevolence from the heart of compassion and the derivation of righteousness from the heart of shame do seem to carry philosophical weight. It is easy to think of benevolence as an extension of compassion—feeling and being compassionate when and as appropriate. This is certainly the sort of benevolence that is at work in the Mencian conception of benevolent government, for example.
It is stranger to us, maybe, to derive righteousness from shame, but an appropriate conception of righteousness is at work in a number of other passages and it could easily be here too. Think of Mencius 7B/31: “If people are able to fill out the heart that bores no holes and jumps no walls, then their righteousness cannot be used up. If people are able to fill out the core of refusing to be addressed informally, they will go nowhere without being righteous.” The first reference seems to be to sexual impropriety (see also 3B/3), the second to humiliating treatment. In both cases, one becomes righteous by refusing to be shamed. Presumably one does this most often by refraining from shameful behaviour, though this and other passages also allow that one could be shamed by what other people do.
It would make things tidier if we could relate deference to ritual in something like this way. (And it would be tidier still if we could make similar sense of Mencius 6A/6’s variant claim.)
Suppose I pass a cup of wine to my father. If I do this because I anticipate that he would like a cup of wine, and I conform to his inclination, then it is reasonable to say that I am deferring to him. However, if this is a ritual, then my father’s desire for a cup of wine is irrelevant: the ritual is unlikely to require that he actually want wine, and I am going to pass the cup even if he does not. I am making a show of deferring to him, perhaps, but I am not actually deferring to him, and of course he is not deferring to me. What we are deferring to is the ritual.
That is how I propose we understand the heart of deference. We defer not to the other participants in the ritual, but to the ritual itself and the tradition of which it is a part. Deferring to the ritual tradition in the right way requires that we engage other psychological resources, of course, but deference to tradition is always fundamental. And similarly with the Mencius 6A/6 variant: we respect or revere not the other participants in the ritual, but the ritual itself as well as the entire ritual tradition.
This is not what scholars typically think of as a Mencian idea, but we do find similar ideas in other passages. 3A/5 rejects Mohist proposals for social change because they do not derive from an instinctive rejection of current practice; in the absence of such a rejection, the passage insists, we should simply follow tradition. 3B/9 portrays a world in disorder, in which beastly philosophers such as Yang and Mo confuse the world like their arguments. This forces Mencius to engage in argument himself when really people should just follow the way of the ancient sages. In these passages at least, deference to and reverence for tradition takes on fundamental importance. If I am right, then it does in Mencius 2A/6 as well.