Conversation

#2: extended healthy (and perhaps fertile) lifespans would reduce some of the harms of a graying society. Longer working lives, lower health care costs. Combined with entitlement reform, it could prevent the crisis of too many sick old people supported by too few working adults.
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#4: The Western lifecycle is currently something like "childhood, adolescence/young-adulthood, parenthood, old age." Add 20 years more of healthy life, and we'll have a new life stage.
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