Certain / Uncertain

Certain                                 -                      Uncertain
Solid                                     -                      Liquid
Ideology                               -                      Mythology
Committed                           -                      Uncommitted

As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality.

[Albert Einstein]
Sidelights on Relativity

What we need now is something for which there isn't a precise word; a form of interpretation in which conviction is compatible with the misgiving that should accompany it.

[Denis Donoghue]
The Arts Without Mystery, p. 106

Someone with a low degree of epistemic arrogance is not too visible, like a shy person at a cocktail party. We are not predisposed to respect humble people, those who try to suspend judgement.

Now contemplate epistemic humility. Think of someone heavily introspective, tortured by the awareness of his own ignorance. He lacks the courage of the idiot, yet has the rare guts to say “I don’t know.” He does not mind looking like a fool or, worse, an ignoramus. He hesitates, he will not commit, and he agonises over the consequences of being wrong.

[Nassim Nicholas Taleb]
The Black Swan, p. 190

Dogmatism: unfounded positiveness in matters of opinion; arrogant assertion of opinions as truths.

Dogmatism is an enemy to peace [...] In the present age [...] it is the greatest of the mental obstacles to human happiness.

The demand for certainty is one which is natural to a man, but is nethertheless an intellectual vice.

If you take your children for a picnic on a doubtful day, they will demand a dogmatic answer as to whether it will be fine or wet, and be disappointed in you when you cannot be sure. The same sort of assurance is demanded, in later life, of those who undertake to lead populations into the Promised Land. 'Liquidate the capitalists and the survivors will enjoy eternal bliss.' 'Exterminate the Jews and everyone will be virtuous.' 'Kill the Croats and let the Serbs reign.' 'Kill the Serbs and let the Croats reign.'

These are samples of the slogans that have won popular acceptance in our time. Even a modicum of philosophy would make it impossible to accept such blood-thirsty nonsense.

But so long as men are not trained to withhold judgement in the the absence of evidence, they will be led astray by cocksure prophets, and it is likely that their leaders will be either ignorant fanatics or dishonest charlatans.

To endure uncertainty is difficult, but so are most of the other virtues. For the learning of every virtue there is an appropriate discipline, and for the learning of suspended judgement the best discipline is philosophy.

Dogmatism and scepticism are both, in a sense, absolute philosophies; one is certain of knowing, the other of not knowing. What philosophy should dissipate is certainty, whether of knowledge or of ignorance.

Instead of saying 'I know this', we ought to say 'I more or less know something more or less like this'. It is true that this proviso is hardly necessary as regards the multiplication table, but knowledge in practical affairs has not the certainty or the precision of arithmetic.

Suppose I say 'democracy is a good thing': I must admit, first, that I am less sure of this than I am that two and two is four, and secondly, that 'democracy' is a somewhat vague term which I cannot define precisely. We ought to say, therefore: 'I am fairly certain that it is a good thing if a government has something of the characteristics that are common to the British and American Constitutions', or something of the sort. And one of the aims of education ought to be to make such a statement more effective from a platform than the usual type of political slogan.

Thinking that you know when in fact you don't is a fatal mistake, to which we are all prone. I believe myself that hedgehogs eat black beetles, because I have been told that they do; but if I were writing a book on the habits of hedgehogs, I should not commit myself until I had seen one enjoying this unappetising diet.

Ancient and medieval authors knew all about unicorns and salamanders; not one of them thought it necessary to avoid dogmatic statements about them because he had never seen one of them.

Many matters, however, are less easily brought to the test of experience. If, like most of mankind, you have passionate convictions on many such matters, there are ways in which you can make yourself aware of your own bias.

If an opinion contrary to your own makes you angry, that is a sign that you are subconsciously aware of having no good reason for thinking as you do.

If some one maintains that two and two are five, or that Iceland is on the equator, you feel pity rather than anger, unless you know so little of arithmetic or geography that his opinion shakes your own contrary conviction. The most savage controversies are those about matters as to which there is no good evidence either way.

So whenever you find yourself getting angry about a difference of opinion, be on your guard; you will probably find, on examination, that your belief is going beyond what the evidence warrants.

A good way of ridding yourself of certain types of dogmatism is to become aware of opinions held in social circles different from your own [...] If you cannot travel seek out people with whom you disagree, and read a newspaper belonging to a party that is not yours.

[Bertrand Russell]
Unpopular Essays ('Philosophy for Laymen', 'An Outline of Intellectual Rubbish'), p.38, 39, 115, 116

Perhaps we're afraid to consider contrary viewpoints because we know that within them is contained a measure of sense. After all, if we spend too long abroad then our own customs may begin to appear strange.

What the traveller, the nomad, knows, is that all positions are relative, and arbitrary; and that every land has its charms.

We have to admit that, strictly speaking, scientific laws cannot be proved and are therefore not certain.

Even so, their degree of probability is raised by each confirming instance; and in addition to the whole of the known past every moment of the world's continuance brings countless billions of confirming instances - and never a single counter example.

So, if not certain, they are probable to the highest degree which it is possible to conceive; and in practice, if not in theory, this is indistinguishable from certainty.

[Bryan Magee]
Popper, p. 21-2

In a beautiful treatise now vanished from our consciousness, Dissertation on the Search for Truth, published in 1673, the polemist Simon Foucher exposed our psychological predilection for certainties.

He teaches us the art of doubting, how to position ourselves between doubting and believing. He writes: “One needs to exit doubt in order to produce science - but few people heed the importance of not exiting from it prematurely… It is a fact that one usually exits doubt without realising it.”

He warns us further: “We are dogma-prone from our mother’s wombs.”

[Nassim Nicholas Taleb]
The Black Swan, p. 129

We can see an ideal of precision, to which we can approximate indefinitely; but we cannot attain this ideal.

Logical words, like the rest, when used by human beings, share the vagueness of all other words. There is, however, less vagueness about logical words than about the words of daily life, because logical words apply essentially to symbols, and may be conceived as applying rather to possible than to actual symbols. We are capable of imagining what a precise symbolism would be, though we cannot actually construct such a symbolism.

Hence we are able to imagine a precise meaning for such words as "or" and "not." We can, in fact, see precisely what they would mean if our symbolism were precise.

All traditional logic habitually assumes that precise symbols are being employed. It is therefore not applicable to this terrestial life, but only to an imagined celestial existence.

[Bertrand Russell]
'Vagueness', The Australasian Journal of Psychology and Philosophy, 1:2, p. 88-9