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Overcoming Bias Commenter's avatar

I agree with piddlesworth's point, though I do not find some of the provided examples. In particular, I do not perceive that tool use requires "reasoning", any more than the creosote bush needed to "reason" in developing toxins which repel competitors and predators, or a skunk needs to reason out its response to a threat. All that's required is that there is a feedback loop which differentially rewards some "behaviors" (in a broad or narrow sense) with expanded market share and a mechanism to persist the more successful. DNA appears capable of this for some amazingly complex behaviors, and mimicry can expand upon that capability on shorter timescales.

However, what characterizes these mechanisms is that the feedback loop must include manifesting some alternatives in the physical world within which outside influences provide the differential selection pressure. What we call "reasoning" is distinguished by using internal abstractions to model the physical world. With reasoning, it becomes possible to adopt a behavior based on (at least vaguely) anticipated results which have not yet been tested with real world feedback - something which DNA and mimicry based adaptive feedback loops cannot do. Of course, often this is combined with real world feedback, in that reasoning generates hypotheses which still need external validation.

This "pre-emptive" generation and winnowing of potential adaptive behaviors provides both more diverse and complex options, and a much faster adaptation timescale - obvious evolutionary advantages which do not necessarily involve persuasion.

Chimpanzees do exhibit some primitive "reasoning" when viewing a problem never before encountered and then choosing an appropriate tool based on geometry, anticipated weight, etc - rather than using just blind trial and error. They show evidence of having an internal model of the physical world, by whose rules they can refine possible actions before taking them. This involves no persuasion.

The incorporation of "reasoning" into human persuasion (along with the often stronger emotional components) would be a natural outcome, once the modeling and rule inferring/using mental abilities exist, and once the "environment" for which humans need to optimize survival strategies includes interpersonal and social structures. As such, the human ability to reason may well have been to some degree shaped by the adaptive value of its use for persuasion. But it does not seem credible to credit persuasion with the origins of reasoning, and the case for that purpose having since become the primary driver seems weak.

A great deal of current research shows that reason and rationality play a smaller part in our individual and collective decision making and in our influence upon each other, than we might like to believe. Confirmation bias and the backlash effect greatly limit the impact of even well reasoned arguments, especially in areas felt to be important to survival and thriving within the tribe. A relatively small portion of the populace develops reasoning as a primary tool in explaining the world to themselves and to others; as others have pointed out, contemporary politics demonstrates that amply.

Nevertheless, reasoning is sufficiently survival positive, that it retains at least some influence in persuasion. However, the internalized models and rules of social systems are much harder to reality-test than the models of the physical environment which generated reasoning as adaptive behavior. Very different models of "how humans work" (politically, economically, socially, psychologically) can coexist in the population more or less indefinitely without selective pressure winnowing them to a "most successful" answer. Hence the many political positions which almost never persuade each other despite massive attempts to show by "reason" that their model is more correct - and the very low interest in facts or reason by adherents to the various ideologies.

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Overcoming Bias Commenter's avatar

Is any of this an advance on Hume?

We’ve probably all had the experience of being on the verge of acting from anger or jealousy, when someone advises us to act reasonably. A typical picture of motivation for action is one in which emotions or desires drive us one way and our reason drives us in another. I have a desire for a tasty but unhealthy dessert, and the voice of reason tells me that I ought not to eat it. I don’t feel like helping at the food bank on Saturday, but conscience tells me that I ought to fulfil my obligation. On this picture, the morally upstanding or prudent person follows the lead of reason, while the morally deficient character caves into desire or emotion.David Hume, in A Treatise of Human Nature, rejects this traditional characterisation of action and its evaluation, offering a remarkable theory in response. He defends the views that the ends or goals of our actions in all cases are given by our “passions,” not by reason, and that the practical role of reason is to figure out how to fulfil these goals. He makes the astounding declaration that “Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them...[Hume] characterised reason not as some mysterious power of grasping truth or of intuiting connections between ideas or thoughts, as some philosophers did, but as the ability either to offer demonstrations or proofs or to make causal inferences.So, first, he shows that reason engaged in demonstration can never be a motive to action. Demonstration is deductive reasoning using necessary truths. Demonstrations are the proofs we use in mathematics and geometry. Mathematics can be applied to the world in the way that engineers use it to solve problems in their work, but knowing the truths of mathematics only, without the addition of a goal or purpose, will not produce a motive to any particular action. Second, Hume asks whether causal reasoning by itself can give motivate action. Causal reasoning, which requires the gathering and assembling of observations, allows us to form beliefs about the world. Do these factual beliefs supply us with motivation to act in particular ways? Say I’m sleepy and I believe coffee can stimulate me. It seems this belief can motivate me to drink a cup of coffee. If so, factual beliefs based on causal reasoning can on their own produce motives. However, Hume notices that such beliefs would have no practical effect on us if we didn’t also have some sort of attraction to the goal achieved by the motivated action – in this instance, staying awake when I’m feeling sleepy. Reason informs me that consuming the caffeine in coffee keeps me awake, but reason didn’t tell me what desires to have. It simply gives me a piece of causal information. Factual beliefs have no influence on our behaviour if they are about things in the world of no concern to us.”

Elizabeth Radcliffe, Ruling Passions

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