The other distinction which she wished to stress was between what she stipulated as “conviction” and “persuasion.” She stipulated that conviction was to be the result of reasonable arguments, whereas persuasion was the result by all other means.
In view of the fact — which Stebbing admitted — that “conviction” and “persuasion” are often used synonymously, it would be clearer to simply prefix the adjective “rational” to these terms. We way then speak of rational persuasion (or conviction), irrational persuasion (or conviction), and non-rational persuasion (or conviction).
Why have these distinctions? The idea of non-rational is to apply to the cognitive life of animals (and we are animals, after all), which includes instinct, association, and conditioning. These cognitive modes are operative as passions — including beliefs, which in humans are shaped linguistically. And there must be some kind of Weltanshauung which people acquire while being raised and living in some linguistic culture. Call it a pre-reflective ideology, if you like. It has also been called an “inherited conglomerate.” In my dissertation on Wilfrid Sellars, I called it an Alpha World, as distinct from a transformed or successor Beta World.
I am reminded here of George Santayana’s idea of “animal faith” and the idea that we must start in “medias res.” I am also reminded of Alfred North Whitehead’s point in “Science and the Modern World,” that each age has a set of presuppositions.
Now, the culture in which you find yourself may be riddled with pseudo-scientific myths, slogans, epigrams, and proverbs — which are false. And the task is to free — at least — yourself from this Platonic cave of bullshit. At the same time there are various bullshitters keeping you in (cognitive) chains.
Bullshitters — intentionally or non-intentionally — use non-rational means to persuade (convince). And — worse — through cognitive dissonance you may even be persuaded to accept that which is irrational. It is irrational to accept a contradiction.
Escape from the cave is through rationalism. I agree with Karl Popper’s description of rationalism in “The Open Society and Its Enemies,” Chapter 24:
Since the terms ‘reason’ and ‘rationalism’ are vague, it will be necessary to explain roughly the way in which they are used here. First, they are used in a wide sense; they are used to cover not only intellectual activity but also observation and experiment. It is necessary to keep this remark in mind, since ‘reason’ and ‘rationalism’ are often used in a different and more narrow sense, in opposition not to ‘irrationalism’ but to ‘empiricism’; if used in this way, rationalism extols intelligence above observation and experiment, and might therefore be better described as ‘intellectualism’. But when I speak here of ‘rationalism’, I use the word always in a sense which includes ‘empiricism’ as well as ‘intellectualism’; just as science makes use of experiments as well as of thought. Secondly, I use the word ‘rationalism’ in order to indicate, roughly, an attitude that seeks to solve as many problems as possible by an appeal to reason, i.e. to clear thought and experience, rather than by an appeal to emotions and passions. This explanation, of course, is not very satisfactory, since all terms such as ‘reason’ or ‘passion’ are vague; we do not possess ‘reason’ or ‘passions’ in the sense in which we possess certain physical organs, for example, brains or a heart, or in the sense in which we possess certain ‘faculties’, for example, the power of speaking, or of gnashing our teeth. In order therefore to be a little more precise, it may be better to explain rationalism in terms of practical attitudes or behaviour. We could then say that rationalism is an attitude of readiness to listen to critical arguments and to learn from experience. It is fundamentally an attitude of admitting that ‘I may be wrong and you may be right, and by an effort, we may get nearer to the truth’. It is an attitude which does not lightly give up hope that by such means as argument and careful observation, people may reach some kind of agreement on many problems of importance; and that, even where their demands and their interests clash, it is often possible to argue about the various demands and proposals, and to reach — perhaps by arbitration — a compromise which, because of its equity, is acceptable to most, if not to all. In short, the rationalist attitude, or, as I may perhaps label it, the ‘attitude of reasonableness’, is very similar to the scientific attitude, to the belief that in the search for truth we need co-operation, and that, with the help of argument, we can in time attain something like objectivity.It is of some interest to analyse this resemblance between this attitude of reasonableness and that of science more fully. In the last chapter, I tried to explain the social aspect of scientific method with the help of the fiction of a scientific Robinson Crusoe. An exactly analogous consideration can show the social character of reasonableness, as opposed to intellectual gifts, or cleverness. Reason, like language, can be said to be a product of social life. A Robinson Crusoe (marooned in early childhood) might be clever enough to master many difficult situations; but he would invent neither language nor the art of argumentation. Admittedly, we often argue with ourselves; but we are accustomed to do so only because we have learned to argue with others, and because we have learned in this way that the argument counts, rather than the person arguing. (This last consideration cannot, of course, tip the scales when we argue with ourselves.) Thus we can say that we owe our reason, like our language, to intercourse with other men.