Simplexity, as I understand it, is the range of solutions living organisms have found, despite the complexity of natural processes, to enable the brain to prepare an action and plan for the consequences of it.
"this book attempts to show that it is up to us to relentlessly inspire the minds of humans to invent a future that will enable humanity to attain a life of more solidarity, a happier life for and with each one of us [...] J. -P. C.