Humanity's Magic Number as 1.5?

Dimensionless constant governing civilization and its potential collapse

Humanity's Magic Number as 1.5?
Preliminary checklist of recognition of 1.5
Potentially significant approximations to 1.5 in practice?
Clarification of the magic square governing human civilization?
Radical possibility of 1.5 resulting from golden ratio design by committee
In quest of a language of proportion as the language of appropriateness
Adaptation of the Uncertainty Principle to the social sciences?
Language of proportion implied by poetic justice
Deflowering of civilization versus Flowering of civilization: an aesthetic contrast?
Spiral of silence and the associated "conspiracy" of silence
Mysterious challenge of doubling, replication and multiplication
References

Never in the history of humankind has a number been so widely publicized in so many forms. As a distance it is now promoted as the key to prevention of the spread of infection in what has been declared a major challenge to global civilization as previously known. As a temperature, constraining its increase is the primary target for climate change strategies -- with the failure to achieve it associated with an expectation of sea level rise of 1.5 feet.

Economic growth over long periods, as GDP, is recognized as increasing at that rate -- expressed as a percentage. The interest rates offered by central banks hover around that figure, if only currently. The sub-fertility replacement rate of 1.5 is a focus of concern with respect to the aging population of many developed countries. And with the light of the Moon framing so many monthly cycles, it is not surprising to discover that it is approximately 1.5 light seconds away.

Constants -- as physical constants -- are understood to be fundamental to the organization of nature and of reality as it is perceived (List of physical constants, Wikipedia). Physics carefully distinguishes dimensionless physical constants as pure numbers having no units attached and having a numerical value that is independent of whatever system of units may be used.

The existence of analogous constants fundamental to psychosocial organization has been less evident, although various indications can be noted (Comprehension of Numbers Challenging Global Civilization, 2014). The most widely cited paper in psychology is that of George Miller (The Magical Number Seven, Plus or Minus Two: some limits on our capacity for processing information, Psychological Review. 1956). In more general terms, potential consequences are explored by David Robson (Has humanity reached 'peak intelligence'? BBC, 10 July 2019; The Intelligence Trap: why smart people make dumb mistakes, 2020). There is therefore a case for exploring whether 1.5 constitutes "a numerical value that is independent of whatever system of units may be used" -- as would appear to be implied by its current widespread importance

A first approach to this possibility is a preliminary literature search to clarify the range of domains in which 1.5 has achieved prominence. This is not sufficient in that the occurrence of that number may be variously disguised. The checklist of obvious examples is therefore followed by an indication of domains in which the role of 1.5 may be inferred as a possibility.

Having framed 1.5 as a "magic number", there is a case for concluding with a speculative focus on one of the most fundamental magic numbers as it features in the simplest magic square as a magic constant -- namely 15. This has the potential merit of indicating how the disparate domains governed by 1.5 may be interrelated.

The speculation can be taken further by exploring the extent to which the focus on 1.5 is a consequence of "design-by-committee". This has unconsciously avoided any effort to highlight a "magic constant" of human-scale significance, namely the golden ratio, of which it is a crude approximation. It would seem that there is a human need for a "language of proportion" to render credible the challenges faced by humanity -- especially if these constitute issues of proportion. Numbers as currently used are readily recognized as an inappropriate language for that purpose.