Doubt in Philosophy and in Science
Doubt has philosophical and as well as scientific relevance. Since ancient times, keen minds have argued for a skeptical evaluation of any proposition that is presented as true. Skepticism generally entertains doubt about knowledge that appears to be, or is presented as, absolutely correct.
Philosophical skeptics wonder about the reliability of our faculties of perception. After all, there are optical illusions and auditory failures, and who is to say that what we think by sight is a snake is not a rope? In all cultures there have been minds that have questioned authority and wondered if what is presented as sacred is true after all.
In the Hindu world, there were Jabali and Charvaka. Jabali instructed prince Rama not to take the proclaimed ethical injunctions seriously, as though they had no ultimate validity. Charvaka was an unbelieving hedonist. Their doubting stance was not appreciated by orthodoxy, but their positive contribution to the culture has been recognized by later scholars. One scholar of them wrote, “In the domain of philosophy, the questions and doubts raised by the Charvakas set problems for all other Schools, made them think more carefully and saved them from much of dogmatism. Every philosopher in India had to satisfy the Charvakas before establishing his own view.”
Pyrrho of the third century BCE was an early Greek skeptic, but doubts about the uncertainty of human knowledge had been expressed by others before and after him. Metrodorus of Chios wrote: “We know nothing, not even whether we know or do not know, or what it is to know and not to know, or in general whether anything exists or not.” The most important idea in Pyrrhoism was that what we take to be real about god and religion is a function of the country, culture, and time in which we are raised, and have no intrinsic truth-content. Many Greek skeptics felt that following a religious custom was normal and natural, without it reflecting any objective reality.
Some scholars in the Islamic world used this admission of uncertainty to refute thinkers who dared to give the Qur’an their reason-based interpretations. The mystical thinker Al-Ghazali attacked rationalists on the grounds that they could never be sure of their rationally derived knowledge. Indeed, his works bearing such entitles as The destruction of philosophy and Revival of the Science of Religion were so powerful in their argumentation that skeptics and rationalists lost ground in the Islamic world. Free inquiry and the scientific spirit were virtually suspended in that great civilization. As one scholar put it “All orthodoxy took comfort from him (al-Ghazali), even Christian theologians were glad to find, in his translated works, such a defense of religion, and such an exposition of piety, as no one had written since Augustine. After him, and despite Averröes, philosophy (rational inquiry) hid itself in the remote corners of the Moslem world; the pursuit of science wanes; and more and more the mind of Islam buried itself in the Hadith and the Koran.”
The undermining of science and reason instigated by some post-modernist philosophers has the potential for snuffing the enlightened perspectives that had been gaining ground slowly in various pockets in civilizations in the last two centuries.
In Europe, the rise of skepticism had the opposite effect. It began to undermine the Christian faith. Thinkers like Abelard had argued that “doubt is the road to inquiry, and by inquiring we perceive the truth.” This view was stated in the context of theology and scholasticism. Skepticism in the sense of a cautious hesitation to accept something as the truth gained ground, as much because of its reasonableness as because of the successes of the newly developing sciences which challenged authority but also incorporated in its methodology a doubting mind-set. Thanks to the writings of thinkers like Michel de Montaigne, René Descartes, Pierre Bayle, David Hume and others, skepticism became more than a modest admission of human inadequacy in arriving at certainty. It led to the loss of faith in many long-upheld religious doctrines, or at least to re-casting them from more enlightened perspectives.
The strength of the scientific enterprise arises from its proclivity to doubt. It subscribes to Cicero’s aphorism that it is by doubting that one arrives at the truth. Scientists rarely defend whatever faith they might have in their enterprise, but they proclaim their proclivity to doubt. This provoked Robert Browning to say:
‘Tis well averred
A scientific faith’s absurd.
Bertrand Russell, the passionate skeptic, said: “William James used to preach the ‘will to believe.’ For my part, I should wish to preach the ‘will to doubt.’ … What is wanted is not the will to believe, but the wish to find out, which is the exact opposite”. One reason for the scientist’s skeptical attitude is that with the passage of time and the acquisition of knew knowledge, older worldviews have often to be given up. There are any number of defunct theories which were once regarded as the truth. That is why, as Hans Reichenbach pointed out: “The development of science, with its repeated elimination of older theories and their replacement by new ones, supplies good reason for … doubt.”
Kenneth Patton expressed the significance of doubt in the science thus: “To doubt is to declare that, lovely as the creations of our fathers have been, they are not sufficient for their sons. It is to declare that there is an upward sweep of history, and that the only way we can justify the inheritance from the past is to improve upon it…. To doubt that the past has uncovered all things is to express the faith that things are still to be uncovered.”