Normalization itself is any process that tends to bring the entire belief space towards a single normal [1]. This occurs whenever the power gradient across the population has a single global maximum/minimum towards which all participants move. Note that while this implies normalization, normalization can happen even when the power gradient is divided [2].
[1]Dictionaries are an excellent example of normalization in spelling. While they are effectively arbitrary (many potential spellings are eliminated in favor of one, without much of an objective basis for the selection of the 'winner'), they yield dramatic improvements in terms of communication: standardized spelling makes both reading and writing easier, and also lets the language drift less through time.
[2]Imagine the landscape resembling a pair of twin peaks: for participants beneath the point in the topology at which the peaks divide, the gradient appears to have a single global maximum, and so the population beneath that point will normalize. Participants above the 'waist' will diverge or polarize.
Having such a 'waist' or inflection point in the normal gradient is useful (this is covered in greater detail below under belief tacking →); when the landscape lacks such diversification, and truly has only a single global maximum, the system tends towards stagnation, the extreme limit of which is totalitarianism →.
Stagnation occurs when a system loses its ideological diversity as the entire population approaches a stable normal. While the word itself is pejorated, note that there's no instrinsic moral value; while stagnation may make a system less responsive to change, and less creative in its endeavours, stagnation is good at preserving useful institutions and creating transparent → belief landscapes.