Thanks to basic entropy, if you're at retirement age, your brain will likely be losing fluid intelligence, the ability to reason, solve problems etc.
Can you trust such people to make important decisions? If you insist and a peak-performance brain, then technically no
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That's not my stance, in the slightest. But if you're going to make rigid rules that insist on individual's brains having the capability of a 'fully developed' one, then you can't ignore the fact that this development can be 'reversed' due to the consequences of age.
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