SKEPTICISM
Critical thinkers adopt a questioning attitude to belief and dogma, and are always ready to challenge other people’s opinions. They do not automatically accept that what they read or hear is true, and they are especially wary of pronouncements made by people in positions of authority. Critical thinkers prefer to think for themselves, using reason and argument to form their own ideas as objectively as possible.
Philosophical skepticism
This questioning attitude is sometimes called ‘skepticism’ – a refusal to take things at face value. Some philosophers, for example, have challenged the common sense view that we live in a world of facts, claiming that nothing exists outside our minds, or that all the material things which we believe exist are merely ideas in the mind of God. And some excessively egotistical philosophers have even claimed that the only thing which exists is their own particular mind.
A more reasonable skepticism claims that all our beliefs about the world are unreliable to some extent and that we have no certain knowledge at all. We can make progress towards the truth, but we can never actually reach it. We should thus be skeptical about everything. In classical times the Pyrrhonian skeptics took this to an extreme, refusing to offer an opinion about anything, not even whether you should try to rescue your teacher when he was stuck head-down in a ditch.
Moderate skepticism
A degree of skepticism is essential if scientific knowledge is to increase. Scientists must remain open to the possibility of new information and new discoveries. The current state of scientific knowledge should always be seen as provisional and not as a final state beyond which no further improvement is possible. This suggests that we should be at least somewhat skeptical about the pronouncements of all authorities whether they are scientific, religious or political.
Science is of course concerned with the natural world. Most scientists assume either that there is no other world or, if there is such a world, that there is nothing that scientists can say about it. And many philosophers have been equally skeptical about the existence of the supernatural. David Hume argued that we should always be skeptical about reports of supernatural events. This is because we know that people are often mistaken and that they sometimes lie.
Common sense
We should not be too skeptical. We should generally trust the evidence of our own senses, our memories and our belief in the regularity of the world. It is reasonable to believe that the sun will rise tomorrow and that the food we ate yesterday will not poison us today. In the practical world of everyday living, excessive skepticism is incoherent because decisions have to be taken and good decisions have to be based on the facts.
It is of course true that the facts are often uncertain, that many situations are complicated, and that we often have to decide on the basis of probability rather than certainty. Even so, it is much better that our decisions should based on the facts rather than on the alternatives – superstition or an irrational skepticism. Relying on the facts not only gives us true beliefs about the world, it also enables us to make our way through it.