Fairly clearly the fundamental-generic ‘equation’ for every human-being to maintain theirself healthy, citizenlike and environmentally-supportive is based upon
One-human-being needs just one-human-living
[In UK currently that might be £300 per week : from which also ‘flows’ the formal-reasoning
“Any-one “needing” twice thagt is (a) only 50% personally-efficient at making-ends-meet in the Lifeplace (128 hrs/week)
but is deluded that s/he is two human-beings […]