Reasoning

Reasoning is the ability to take pieces of relevant information and mentally put them together to reach a logically defensible conclusion, defensible at least to those doing the reasoning. Reasoning can be used to confirm conclusions already arrived at or to create new conclusions, conclusions which are a synthesis of existing information. Reasoning, outside of mathematics, does not necessarily create a conclusion that is unassailable. It creates a conclusion that is, until superseding evidence or more logical propositions are introduced, at least plausible. Even if new evidence is produced, there is no guarantee that this conclusion will change. In mathematics, reasoning is based on the ability to arrange propositions in a logically proper sequence in order to arrive at a conclusion that is considered the only one possible. We will see that human reasoning outside the realm of mathematics is often deeply flawed and devoid of logical consistency. Moreover, we will consider the hypothesis that reasoning isn’t so much about arriving at a conclusion as it is justifying the preferences of those doing the reasoning.

Evolutionary Origins and Functions of Reasoning

It could be fairly said that the deep origins of reasoning lie with the need to deal with the issues and problems with which our genus is typically confronted. In our earliest ancestors, these issues and problems were very often matters of life or death. It was therefore reproductively advantageous for a line of advanced primates to be able to analyze situations and piece together a plan of action. An American psychologist, introducing a paper on the subject, put it this way:

First, solving problems of social competition and cooperation have direct impact on survival rates and reproductive success. Second, the social structure that evolved from this pressure is the dominance hierarchy. Third, primates that live in large groups with complex dominance hierarchies also show greater neocortical development, and concomitantly greater cognitive capacity. These facts suggest that the necessity of reasoning effectively about dominance hierarchies left an indelible mark on primate reasoning architectures, including that of humans.¹

Natural selection favored reasoning. The reasons for this have not been fully ascertained. Two philosophers who have studied reasoning in depth argue that the principle function of reasoning “is to devise and evaluate arguments intended to persuade”. This, they contend, made reasoning adaptively useful in settings, such as human social groups, where verbal communication is so vital. They stress that reasoning is not principally concerned with finding the truth of a matter. It is, rather, a way for the people making an argument to defend their opinion and to persuade others. It produces decisions that can be justified easily, but not necessarily the best decisions. And sometimes reasoning works backwards: it can be used to support a conclusion that has already been made.²

Another researcher, reacting to this work, put forth the hypothesis that reasoning emerged as a way of fostering unity of outlook within social groups. In this view, it was a way of getting everyone on the same page, so to speak. As the author put it, “It helped our ancestors share intentions, collaborate more successfully—and thereby propel a social species toward ultrasociality.”³

If we are looking for specific neural correlates of reasoning, we face challenges. The opinion among some researchers is that reasoning can take place in multiple ways and involve a very wide array of interacting brain processes. A researcher in Spain has noted that even the most sophisticated tests, done with the most advanced equipment, have been unable to find a specific brain location in which reasoning takes place.⁴

There are scientists investigating hypotheses that the hemispheres of the brain have distinct functions in the reasoning process. One hypothesis is that the left hemisphere excels at abstract reasoning and the right hemisphere draws more on emotional memories in its reasoning process. Another hypothesis argues that if the right hemisphere fails to retrieve emotional experiences, the left hemisphere applies rules of logic.⁵

There is a distinction between inductive reasoning and deductive reasoning. Inductive reasoning is based on gathering evidence and observations. This evidence and these observations are used to form a hypothesis. Deductive reasoning is based on a broad principle which is used to reach a conclusion, a conclusion the accuracy of which is dependent on the broad principle’s validity. We might suppose that an individual using inductive reasoning would, upon encountering a situation, note various aspects of it, perhaps drawing on previous experiences and knowledge, and try to piece together an explanation of the situation. A person relying on deductive reasoning might immediately categorize a situation, and evaluate the events being encountered within the context of that category. We should bear in mind that there may be considerable overlap in these methods of reasoning, and that aspects of both of them may be employed by individuals assessing situations.

Common Limitations and Errors in Human Reasoning

Many flaws are common in human reasoning. If people misperceive an event (such as mistaking a comet or meteor trail for an alien invader) their reasoning process will be based on false premises. Another example of a false premise is seeing those who have been denied any education, and reasoning that such people are naturally intellectually inferior. Humans may possess severely limited information, which can hamper their ability to assess a situation. As we will see in greater detail elsewhere, errors inherent in the physiology of the brain can mislead humans profoundly. Emotional issues can arise, clouding our judgment, and leading us toward a conclusion that we may find desirable rather than one which fits available facts. We might “cherry pick” information, choosing only those facts which bolster our preferences or listening only to those with whom we agree. (This is called confirmation bias.) In short, humans tend to have cognitive biases that affect their ability to reason accurately. There are many examples of how these biases operate and manifest themselves. Two researchers in cognitive neuroscience offer the following comprehensive definition:

Cognitive biases are systematic cognitive dispositions or inclinations in human thinking and reasoning that often do not comply with the tenets of logic, probability reasoning, and plausibility. These intuitive and subconscious tendencies are at the basis of human judgment, decision making, and the resulting behavior. Psychological frameworks consider biases as resulting from the use of (inappropriate) cognitive heuristics that people apply to deal with data-limitations, from information processing limitations, or from a lack of expertise. Neuro-evolutionary frameworks provide a more profound explanation of biases as originating from the inherent design characteristics of our brain as a neural network that was primarily developed to perform basic physical, perceptual and motor functions, and which also had to promote the survival of our hunter-gatherer ancestors.⁶

We are reminded here, once again, that the brain evolved to keep us alive long enough to share our genetic material. Cognitive biases are apparently a mechanism for facilitating this purpose. It’s as if our minds seek to reassure us that our judgment of a situation is accurate. Such biases also help us validate our decisions. The number of such biases uncovered by researchers is formidable. Some lists contain more than one hundred.

Heuristics and Reasoning

By heuristics we mean, basically, the mental short cuts people use to make decisions. Many observers simply call them “rules of thumb” (to use an English-language idiom). They are not truly rigorous in terms of logic but they seem to be ubiquitous in human life. There is a debate among those who research reasoning about whether humans reason in a rational way. Many researchers argue that heuristics cause people to come to irrational decisions. There are, however, those who dissent from this analysis. A professor of philosophy and history maintains that people are often being held to an abstract ideal of reasoning that can’t be realized in actual situations. Heuristic methods, he argues, can lead to practical, real life conclusions, and for those untrained in the fine points of epistemic reasoning [the study of the use of logical rules to analyze arguments and beliefs] heuristic reasoning is highly useful. He puts it directly:

1. Heuristic reasoning often maximizes accuracy for limited reasoners, especially in information-rich environments.

2. Maximizing accuracy is the overriding rational good in these reasoning contexts; so

3. Heuristic reasoning often maximizes rationality for limited reasoners.⁷

Occam’s Razor as a Reasoning Technique

Occam’s (or Ockham’s) Razor is associated with Late Medieval English philosopher William of Ockham (c.1287-1347). It is, to oversimplify it, a sort of test that can be applied to conflicting explanations of events. The principle behind it is that the simplest explanation of an event (or to be more precise, the explanation with the fewest elements) tends to be the truth. This makes it powerfully appealing to most people. A group of scientists studying human decision-making have explored why people tend to prefer simplicity when explaining the causes of events. According to their research, this preference is not cultural. As they put it:

…people tend to use simplicity preferences when making decisions, and…these preferences do not seem to be simply consequences of learning specific tasks but rather an inherent part of how we interpret uncertain information. This tendency has important implications for the kinds of computations our brains must use to solve these kinds of tasks…

They go on to explain that humans seem to focus on those elements of a situation which are easiest to explain, and those which seem to encompass the largest number of its elements.⁸

Belief Perseverance

Do humans generally change their conclusions based on facts they did not originally have? If human reasoning relies on the gathering of facts, we would imagine that additional (or even contradictory) information might affect that reasoning and the conclusions derived from it. But the research on this shows that this is not generally the case. Belief perseverance is the tendency most humans have to cling to their initial beliefs, even in the face of strong evidence against those beliefs.⁹ Now, it should be said that there is some evidence that educated psychology study volunteers are amenable to changing their views when presented with persuasive evidence.¹⁰ I have to wonder, however, how representative of the general population such people are.

Humans reason at a level of which no other animal is capable. But outside the realms of pure logic, peer-reviewed science, and mathematics, that reasoning is flawed, deeply imperfect, a tool of persuasion, and a method of fostering group unity. The human brain seems to instinctively seek out confirmatory evidence, and this can lead not only to erroneous but even disastrous outcomes. Yet, in everyday life, basic human reasoning can be useful in limited contexts. Our reasoning is permeated with emotional influences, specifically the desire for good outcomes. In fact, emotion seems to color every aspect of the human mind and influence every part of our behavior, even when we believe we are being completely “objective” (however that term is defined). It is to the vast subject of human emotion that we now turn. In doing so, we will encounter aspects of ourselves which may be difficult for us to acknowledge, but which are nonetheless part of the basic foundation of who we are as human beings.

 

1.   https://www.denisecummins.com/uploads/1/1/8/2/11828927/cumminsmm1996pdf.pdf

2.   http://www.dan.sperber.fr/wpcontent/uploads/2009/10/MercierSperber

      Whydohumansreason.pdf

3.    https://www.academia.edu/115215551/Why_we_reason_intention_alignment_

and_the_genesis_of_human_rationality

4.   https://pmc.ncbi.nlm.nih.gov/articles/PMC4408754/#sec3

5.   https://jamanetwork.com/journals/jamaneurology/fullarticle/782167

6.   https://www.sciencedirect.com/topics/neuroscience/cognitive-bias

7.   https://philpapers.org/archive/KARRWH.pdf

8.   https://pmc.ncbi.nlm.nih.gov/articles/PMC9882019/

9.   https://research.com/education/why-facts-dont-change-our-mind#2

10. https://www.sciencedirect.com/science/article/abs/pii/S0022103118304529?via%3Dihub