The Problems of Philosophical Consistency and Rationality

Reuben Thomas

2nd November 1991

Philosophy is often viewed as a science, and philosophers employ rigorous reasoning, often with the assistance of formal logic. For some considerations, such as syllogisms and the structure of time, this sort of reasoning is appropriate, but when debating the fundamentals of philosophy, for example the existence of god or epistemology, and especially when constructing a personal philosophy, this type of reasoning can be unhelpful, and even dangerous.

The attraction of consistency and rationality is that they offer a complete solution to all life’s problems, which can be resolved instantly, and with unwavering certitude. A fully rational and consistent philosophy is elegant, simple, and universal, with the added attraction of being scientific. Such philosophies are implied in the ten commandments, in law, and in many other philosophical systems, such as utilitarianism. However, the tenure of such a philosophy in the face of an irrational, inconsistent universe results in narrowmindedness, inflexibility, and inhumanity.

Rationality is to consider a situation logically, and, from certain premises, often justified in terms of other, more basic axioms, to deduce the correct course of action to take, or opinion to hold. One example of its dangers is solipsism, the belief that one’s self is the only thing that exists. There is no way of proving this belief to be false, there is not even any evidence that it is false. Thus, rationally, it is an excellent belief to hold, and indeed a solipsistic statement, “Cogito ergo sum”, was the basis of Descartes’ philosophy.

Yet solipsism has frightening consequences. “There is a monstrous difference between thinking of another person as ontologically real...and thinking of that person as a useful construct based on the patterns of your phaneron. [the world of our experience]” wrote Martin Gardner.1 How can you behave ethically (except for expediency) when other people do not exist? And not just solipsism, but rationality in general, leads to a cold, clinical attitude towards life.

Consistency is similar to rationality, but less extreme: it does not require reasoning, but only that all equivalent situations are dealt with in exactly the same manner. As a result, it suffers from the same sorts of problems. For example, the Children Act (1989) states that “a fixed policy regarding punishments [in schools] must be made accessible to staff and parents,” that is to say, punishments must be consistent.2 But most people would agree that that is wrong: that the punishment should fit not only the crime, but the criminal, taking into account his previous behaviour, his current emotional circumstances, and so on. Accepting consistency means losing an ability to differentiate between individuals, and to treat each on his own terms. More seriously, whole cultures may thus be judged barbaric and worthy of extermination, by ignoring their own system of ethics, and judging them according to ours: this reasoning has been the cause of many wars and other human tragedies throughout history.

There are other, more pragmatic, reasons why consistency and rationality are a hindrance. Consistency especially leads to inflexibility, narrowmindedness, and an inability to change views. This results in a dull character, unlikely to succeed, if unlikely to fail, unable to take advantage of opportunities. On a larger scale, consistency results in intellectual and social stagnation, and ultimately to cultural extinction. Even from a rational point of view this is not a good result. Rationality leads to a lack of imagination, of inspiration, and, while the result may not be as disastrous as consistency (for rationality does not necessarily imply consistency), it certainly makes for a humdrum existence, and a loss of humanity, so important at a time when the human scale is rapidly being submerged by technology.

There are, however, still philosophical problems with discarding consistency and rationality. Their very failings are strengths in helping to simplify complex arguments, and leave them without contradictions. Without rationality and consistency, you cannot progress from axiom to theorem. I would argue that this point of view is itself too rational, and Martin Gardner writes “in the absence of compelling counterarguments, emotions can be legitimate grounds for metaphysical jumps”. Why, after all, should we accept reason as the only basis for philosophical argument, and exclude the other half of our nature from debate about crucial issues?

Support for this idea is implicit in the observation that throughout history, there have been hardly any philosophers who professed solipsism, certainly no sane ones, and similarly philosophers are notorious for at least appearing to contradict themselves. For example, Thomas S. Kuhn claims on the one hand that different paradigms are incommensurable, and on the other that there can be communication between proponents of different paradigms. More fundamentally, it is noticeable that often the disciples of any one philosopher always proclaim his philosophy in a more extreme form than the philosopher himself. This is because there is more to most philosophies than is written down: they also consist in the underlying assumptions of their author, which he may feel are too obvious to require stating, or of which he may even be unaware.

Most importantly, man is an emotional creature, and it is ridiculous to ignore his capacities and capabilities in that direction. The need for emotion does not need to be defended to the rationalists: if we did not need emotion to survive, we should not have it, we should have evolved out of it. Emotion is not like the appendix, a mere encumbrance, but manifestly directs much of our lives. Inconsistency and irrationality can be strengths, providing unorthodox solutions to problems which may have seemed insoluble: most of the great scientific and mathematical discoveries ever made were the result of sudden inspiration, which rational processes can aid, but never create, and there are many anecdotes of miraculous escapes from calamity which relied on luck and daring. Moreover, even a consistent rationalist can aim to be happy, but happiness is not a goal that can be achieved purely through rationality and consistency, is not even easy to achieve purposely, but is most often attained unlooked for by people who just get on with living, exploring what is possible, and exercising that gift which is our unique privilege: their humanity.


Thanks once more to Jeremy Douglas for proofreading, and making suggestions.

Gardner, M., The WHYS of a Philosophical Scrivener
Quelle No. 53, Child’s Play, wording and italics from article, not quoted directly from the Act.
This document was translated from LATEX by HEVEA.

Last updated 2006/05/01