[alankay]

The 7±2 was thoroughly proven for sequences of numbers, letters, words, etc. by George Miller and followers. Much has been done since, and this shows that for many things we can handle fewer chunks. That "7±2" is still used for the larger idea of "cognitive load" makes it a cliche and a metaphor.

So it is just as true as I intended. We live in a world of unsupported opinion. I'm 77 and from a world in which one was supposed to have considerable support for an opinion before voicing it. I realize that this is out of step these days, and especially with web fora.

[wahern]

To my mind a cliche refers to an archaic metaphor. Archaic because it out-lives the discarded conceptual framework it describes, and therefore no longer communicates anything of substance. Worse, such cliches often perpetuates err in conceptualizing an issue.

Qualitatively and quantitatively, working memory capacity strongly reflects limitations of so-called executive attention and, more generally, executive function. See, e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2852635/ ("Based on the finding that WMC and EF tasks shared substantial common variance, we argue that the current data provide evidence for reciprocal validity for both of those constructs. Reciprocal validity can be defined as a particularly strong form of construct validity, such that two constructs that are strongly empirically related to one another lend support to the theoretical reality of each other.").

AFAIU, the 7±2 quantity is still both valid in its original context and in communicating something substantive about more complex phenomena. Of course, depending on how you "chunk" a "concept" the number quickly becomes meaningless, but that's a game of semantics. The more sophisticated definitions of chunking that one would use to invalidate 7±2 necessarily invoke broader, more speculative models, given that so much about cognition is still unknown. I can't see how one could fairly use such models to invalidate the 7±2 rule, which remains literally and meaningfully true for "chunks" as originally defined. 7±2 communicates something both qualitatively and quantitatively true about something very specific--words, letters, numbers, etc--and about larger phenomena in cognition--constraints on higher-order cognitive processes are reflected by a phenomenon which has a fixed absolute limit, 7±2, in relation to these easily identifiable and measurable inputs--words, letter, etc.

In other words, referring to 7±2 is saying something both concrete and meaningful. Moreover, the conceptual model it invokes is still the dominant framework, if only because the rule circumscribes what it purports to describe, even in common usage. Nobody mistakes a heuristic for determining the length of a phone number (a derivative "rule" which is far more susceptible to the monicker, cliche) with a limit on our innate capacity for conceptualizing Relativity. Examples which invalidate the rule actually muddy the waters by drawing in more incomplete and uncertain premises, exemplifying what the 7±2 rule gets right about how best to communicate something of substance about such a complex and incomplete field of study. Of course, there are limitations to what you can extrapolate from 7±2, but that would be understood.

That's why I think it unfair to disparage application of the "7±2" phenomenon as cliche. Whatever one's specific definition of cliche, I think it's fair to say that labeling such usage "cliche" is to disparage it. I think such disparagement is unfair. It's rare for a simplified anchor to a complex field to retain such validity and power. But ultimately I guess my point rests on what might be an idiosyncratic definition of cliche.