(This is a comment that has been turned into a post.)

I have seen much talk on Less Wrong of “development stages” and “Kegan” and so forth. Naturally I am skeptical; so I do endorse any attempt to figure out if any of this stuff is worth anything. To aid in our efforts, I’d like to say a bit about what might convince me be a little less skeptical.

A theory should explain facts; and so the very first thing we’d have to do, as investigators, is figure out if there’s anything to explain. Specifically: we would have to look at the world, observe people, examine their behavior, their patterns of thinking and interacting with other people, their professed beliefs and principles, etc., etc., and see if these fall into any sorts of patterns or clusters, such that they may be categorized according to some scheme, where some people act like this [and here we might give some broad description], while other people act like that.

(Clearly, the answer to this question would be: yes, people’s behavior obviously falls into predictable, clustered patterns. But what sort, exactly? Some work would need to be done, at least, to enumerate and describe them.)

Second, we would have to see whether these patterns that we observe may be separated, or factored, by “domain”, whereby there is one sort of pattern of clusters in how people think and act and speak, which pertains to matters of religion; and another pattern, which pertains to relationship to family; and another pattern, which pertains to preferences of consumption; etc. We would be looking for such “domains” which may be conceptually separated—regardless of whether there were any correlation between clustering patterns in one domain or another.

(Here again, the answer seems clearly to be that yes, such domains may be defined without too much difficulty. However, the intuition is weaker than for the previous question; and we are less sure that we know what it is we’re talking about; and it becomes even more important to be specific and explicit.)

Now we would ask two further questions (which might be asked in parallel). Third: does categorization of an individual into one cluster or another, in any of these domains, correlate with that individual’s category membership in categories pertaining to any observable aspect of human variation? (Such observable aspects might be: cultural groupings; gender; weight; height; age; ethnicity; socioeconomic status; hair color; various matters of physical health; or any of a variety of other ways in which people demonstrably differ.) And fourth: may the clusters in any of these domains sensibly be given a total ordering (and the domain thereby be mapped onto a linear axis of variation)?

Note the special import of this latter question. Prior to answering it, we are dealing exclusively with nominal data values. We now ask whether any of the data we have might actually be ordinal data. The answer might be “no” (for instance, you prefer apples, and I prefer oranges; this puts us in different clusters within the “fruit preferences” domain of human psychology, but in no sense may these clusters be arranged linearly).

Our fifth question (conditional on answering yes to all four of the previous question) is this: among our observed domains of clustering, and looking in particular at those for which the data is of an ordinal nature, are there any such that the dimension of variation has any normative aspect? That is: is there a domain such that we might sensibly say that it is better to belong to clusters closer to one end of its spectrum of variation, than to belong to clusters closer to the other end? (Once more note that the answer might be “no”: for example, suppose that some people fidget a lot, while others do not fidget very much. Is it better to be a much-fidgeter than a not-much-fidgeter? Well… not really; nor the reverse; at least, not in any general way. Maybe fidgeting has some advantages, and not fidgeting has others, etc.; who knows? But overall the answer is “no, neither of these is clearly superior to the other; they’re just one of those ways in which people differ, in a normatively neutral way”.)

Finally, our sixth question is: does there exist any domain of clustering in human behavioral/psychological variation for which all of these are true:

• That its clusters may naturally be given a total order (i.e., arranged linearly);
• That this linear dimension has normative significance;
• That membership in its categories is correlated primarily with category membership pertaining to one aspect of human variation (rather than being correlated comparably with multiple such aspects);
• That in particular, membership in this domain’s clusters is correlated primarily with age.

Note that we have asked six (mostly^[1]) empirical questions about humanity. And we have had six chances to answer in the negative.

And note also that if we answer any of these questions in the negative, then any and all theories of “moral development” (or any similar notion) are necessarily nonsense—because they purport to explain facts which (in this hypothetical scenario) we simply do not observe. Without any further investigation, we can dispose of the lot of them with extreme prejudice, because they are entirely unmotivated by the pre-theoretic facts.

So, this is what I would like to see from any proponents of Kegan’s theory, or any similar ones: a detailed, thorough, and specific examination (with plenty of examples!) of the questions I give in this comment—discussed with utter agnosticism about even the concept of “moral development”, “adult development” or any similar thing. In short: before I consider any defense of any theory of “adult development”, I should like to be convinced of such a theory’s motivation.