Reason is a massive survival advantage. Because it let’s you understand that what is true today is true again tomorrow. It let’s you notice that the area around that tree flooded during the rain so it’s probably not a good place to shelter from the next rain storm. It let’s you understand that the berries on that bush made you puke so you probably shouldn’t eat them anymore. It’s what let’s you not be my cats when the wife is out of town hurrying into the bedroom in the morning expecting to find her even though she didn’t go into the bedroom last night. It allows you to process the past to predict the future and plan accordingly.
Nice post. You are pointing out how reason is not a trait.
It does illustrate why the concept of “reason” is meaningless or superfluous in an evolutionary context.
To an evolutionist what we call reason is instinctual stimuli-response, selected behavior.
It’s no different than microorganism chemo-taxis.