[undershirt]

Maybe a “heresy” is simply that which is valid but not sound.

The ecumenical councils were in some ways the means by which they imprisoned and cut away what is valid (according to some presuppositions) to leave only what is sound (according to the presuppositions of the apostles).

It is the opposite of enlighenment carte-blanche thinking, to take a multivariate attack on delusion through reason anchored in a legacy of wisdom. Too bad the schism broke our understanding of this, but it is still preserved in Eastern Orthodoxy.