Yes, reflex actions are rational – we don’t need to have intelligence to perform them. When you have your hand on a hot stove, you just take it off without thinking. Those reactions come from your spinal cord rather than from your brain. Intelligence and thinking processes are done at the brain, whereas all reflex actions are done by the spinal cord. It is rational in that it is optimizing its payoff. It is intelligent in that there were two options.
(1) remove hand
(2) remove hand and re-analyze
Anything that makes a decision is intelligent.
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