Google gave me mostly AI slop and pop psychology, but this article is an in-depth summary of the literature on the topic of inner speech, for anyone interested (and dedicated - it’s long and very technical).

It doesn’t seem to justify dichotomizing people into those who “have it” and those who don’t. Research looks mostly focused on what cognitive or developmental purpose it serves.

Inner speech can be defined as the subjective experience of language in the absence of overt and audible articulation. This definition is necessarily simplistic: as the following will demonstrate, experiences of this kind vary widely in their phenomenology, their addressivity to others, their relation to the self, and their similarity to external speech.

So, it’s on a spectrum, highly subjective, and difficult to talk about with precision.

I personally do not normally think in words, but I certainly rehearse/relive conversations. I also complain to myself with words when I am really miserable, I think it’s comforting to “say it out loud” (inside). Do I have an inner monologue?

Apropos since this has always been my mental image of RACI modeling:

Lesgo?

index -> indices matrix -> matrices codex -> codices appendix -> appendices

I think that would be the plural of Kleenus.