I've suggested that the relationship between the content of a MUSH and its group of participants resembles the relationship between the content of a joint faith-belief and its group of followers. First, the group is brought together through their common relationship to the content. Second, the group is also the active source for explaining, refining, and expanding the content. Third, the group itself determines the explicit and implicit rules for what the content is or can be—although everyone probably doesn't have equal influence on these determinations.
On the other hand, the differences are impossible to miss. Consistent with its technological era, a MUSH's outward expression is limited to typewriter-like lines of text data (including rough "images" created out of carefully arranged punctuation). Its inward mechanism is software running on a computer that's exposed to the internet. Interactions with it consist of relatively short bursts of digitized signals speeding back and forth over great distances of transmission lines. The endpoint is marks on a screen. Without question, the experiences of MUSH participants are drastically unlike the typical experiences of followers of joint faith-beliefs. These experiences seem comparatively lifeless, spare, and remote, even alongside the various other experiences enabled by internet connections. Someone could easily assume a corresponding deficiency in the subjective value of these experiences.
However, that assumption is at least a little mistaken. It doesn't recognize that the group supporting the MUSH is completely unforced, so the group's continuing existence signifies worthwhile value. Somehow the group gains a motivating psychological "payoff". It could come in many subtle forms: fascination with the content, companionship with others, gratification of helping to make a wonderful addition, etc. Once again, a MUSH has an illuminating parallel to joint faith-beliefs. Through payoffs that are purely (and admittedly) psychological, it can have appeal independent of its lack of factualness.
This parallel isn't mentioned in order to foolishly claim that the two categories have identical payoffs or that one can substitute for the other. A MUSH is a microcosm, a more modest example in every way. Actually, the thought-provoking surprise is that its payoffs are appreciable nonetheless. Although it's a leisure hobby, revolving around fiction, operating through a primitive medium...it's sufficient to spur a persistent human group to maintain its existence. Hence it reiterates major defects in trying to seriously corroborate beliefs on the basis of mental effects: 1) countless other stimuli can produce mental effects of the same kind, if not the same vividness, 2) usually the mental effects themselves are either nebulous, or packed with formulaic echoes of the subject's expectations. Greater intensity of mental effects and psychological payoffs solely position the category of joint faint-beliefs on a farther end of a MUSHy continuum, not reposition it on another continuum entirely. (Phrased in internet popular lingo, it's a MUSH...in which things just got real.)
Likewise, an unending array of human pursuits/ideas could serve as supplementary illustrations that joint faith-beliefs aren't exceptional. The variations are virtually unlimited, with contrasting levels of formality, realism, grandiosity, popularity, exclusivity, zeal, style, intricacy, comprehensiveness, mood, comfort, rigidity, difficulty, age, methodology. In any case, the conclusion stands. The psychological payoffs of joint faith-beliefs aren't satisfactory rationales for countering the possibility that the core is MUSHy after all.