editor, Administrators
2,020
edits
Changes
Jump to navigation
Jump to search
no edit summary
Hume took Newton’s opposition to demonstrative science much further, questioning the idea of a necessary mechanical connection between cause and effect. "Let an object be presented to a man of ever so strong natural reason and abilities;" he wrote, "if that object be entirely new to him, he will not be able, by the most accurate examination of its sensible qualities, to discover any of its causes or effects. Adam [the Biblical first man], though his rational faculties be supposed, at the very first, entirely perfect, could not have inferred from the fluidity and transparency of water, that it would suffocate him, or from the light and warmth of fire, that it would consume him. No object ever discovers, by the qualities which appear to the senses, either the causes, which produced it, or the effects, which will arise from it; nor can our reason, unassisted by experience, ever draw any inference concerning real existence and matter of fact." [[CiteRef::Hume (1975)|p. 109-110]] The connection between a cause and its effect was learned by observation and experience, and could not be shown by demonstrative argument. [[CiteRef:: Bell (2009)]][[CiteRef::De Pierris (2006)]][[CiteRef:: Morris and Brown (2016)]]
Having rejected demonstrative knowledge for the natural world, Hume recast Aristotle's distinction between scientific knowledge and opinion as a distinction between '''relations of ideas''' and '''matters of fact'''. [[CiteRef::Hume (1975)| pp. 108-113]] Relations of ideas are ''a priori'' truths that are discoverable independent of experience, and can be shown with certainty by demonstration or intuition. Because they must be true in any world, they cannot provide any new information about our own world. Relations of ideas are confined to the formal sciences of mathematics, geometry, and logic. Examples of such statements include 'a square’s sides add up to 360 degrees', '1 + 1 = 2', or, 'all bachelors are unmarried'. Relations of ideas can not be denied as their denial would imply a contradiction in their very definition. [[CiteRef:: Morris and Brown (2016)]][[CiteRef::Hume (1975)| pp. 108-113]] Matters of fact, by contrast, are ''a posteriori'' statements based on knowledge obtained from the world through observation or experience. Examples of such statements include 'the sky is blue', or 'water is odourless'. Note that the contrary of a matter of fact is not something impossible. The claim that ‘the sun will not rise tomorrow’ is just as intelligible as, and no more contradictory than the claim that ‘the sun will rise tomorrow’. The two claims are only distinguishable by observation and experience. [[CiteRef::Morris and Brown (2016)]][[CiteRef::Hume (1975)| pp. 11]] Unlike relations of ideas, matters of fact do not hold true in all possible worlds and cannot be established by demonstration. They can never be known with certainty. Hume’s new categories of knowledge made it clear that natural philosophy, since it relied on knowledge of matters of fact, could never aspire to the kind of certainty that Aristotle supposed for scientific knowledge, and should be content with the modest sort of knowledge available through Newton’s inductive method. [[CiteRef::De Pierris (2006)]]
==== Hume’s problem of induction ====
2) Therefore, the future will be like the past.
But this argument itself relies on induction, ; the very mode of argument it seeks to justify. As Hume put it: "According to my account, all arguments about existence are based on the relation of cause and effect; our knowledge of that relation is derived entirely from experience; and in drawing conclusions from experience we assume that the future will be like the past. So if we try to prove this assumption by probable arguments, i.e. arguments regarding existence, we shall obviously be going in a circle, taking for granted the very point that is in question." [[CiteRef::Hume (2008)| p. 16]] He concluded that "the conclusions we draw from experience are not based on reasoning or on any process of understanding". [[CiteRef:: Hume (2008) |p. 15]] But induction is necessary for the conclusions that we draw, not only in Newtonian science, but also in our daily lives, which would not be possible without it. Hume concludes that we are compelled to use induction by a powerful natural instinct, or more specifically his principles of association. "All these operations" he wrote, "are species of natural instincts, which no reasoning… is able either to produce or prevent". [[CiteRef::Hume (1975)| p. 46-47]] Humans must, Hume concludes, rely on "the ordinary wisdom of nature", which insures that we form beliefs "by some instinct or mechanical tendency", rather than trusting "the fallacious deductions of our reason". [[CiteRef::Hume (1975) |p. 55]] In keeping with this naturalistic conclusion, Hume devotes an entire section of the ''Enquiry'' to an argument that non-human animals also learn by induction. He writes that "it seems evident that animals, like men, learn many things from experience, and infer that the same outcomes will always follow the same causes". [[CiteRef::Hume (2008)| p. 53]] Hume’s conclusion was a radical challenge to the central role assigned by rationalists like Descartes and Leibniz to reason in the production of our knowledge, and is seen today as a step towards modern ideas in cognitive science and neuroscience.[[CiteRef::Biro (2009)]]
==== Hume's skepticism about theological knowledge ====
In the early modern Christian Europe, theology and natural philosophy were not deemed foreign to one another, but rather seen as compatible parts of an integrated [[Scientific Mosaic|mosaic]] of knowledge. [[CiteRef::Barseghyan (2015)|p. 65]] Theological knowledge derived from observations of nature and its supposed design, the supposed divine revelation of the Bible, and supposed miraculous events where God had intervened directly in human affairs. [[CiteRef::Fieser (2016)]] As a thoroughgoing empiricist, Hume questioned all these sources of knowledge, and rejected theological knowledge as impossible.
In a letter to Henry Home (1696-1782) published in 1737, Hume confessed that he intended to include a skeptical discussion of miracles in his ''Treatise'' but left it out for fear of offending readers. Critics of religion in eighteenth century Europe faced the risk of fine, imprisonment, or worse. [[CiteRef::Fieser (2016)]] Hume did later publish his critique in the ''Enquiry'' in 1748. He wrote that "A wise man...proportions his belief to the evidence" [[CiteRef::Hume (2008)| p. 56]] and drew the conclusion that "A miracle is a violation of the laws of nature; and because firm and unalterable experience has established these laws, the case against a miracle is- just because it is a miracle- as complete as any argument from experience can possibly be imagined to be....No testimony is sufficient to establish a miracle unless it is of such a kind that its falsehood would be more miraculous than the fact it tries to establish...When anyone tells me that he saw a dead man restored to life, I immediately ask myself whether it is more probable that this person either deceives or has been deceived or that what he reports really has happened...If the falsehood of his testimony would be more miraculous than the event he relates, then he can claim to command my belief or opinion, but not otherwise". [[CiteRef:: Hume (2008)| p. 58-59]] The claim that a dead man was restored to life is, of course, central to Christian theology. Hume's arguments have gained a relevance beyond theological knowledge, and have been espoused as a [[methodology]] for evaluating other sorts of extraordinary or surprising claims, such as claims of paranormal occurrences or of extraterrestrial intelligence. They are succinctly summarized by the maxim, popularized by the twentieth century astronomer Carl Sagan (1934-1996), that "extraordinary claims demand extraordinary evidence". [[CiteRef::Sagan (1979)| p. 62]][[CiteRef:: Deming (2016)]] In 1757, Hume published an essay entitled ''The Natural History of Religion'' which was the first systematic attempt to explain religious belief solely in terms of what we would call psychological and sociological factors. [[CiteRef::Fieser (2016)]]
Having called revealed religion into question by doubting miraculous events, Hume's most ambitious skeptical attack on the possibility of theological knowledge was turned his attention to natural theology in his ''Dialogues concerning Natural Religion'', which he arranged to have published posthumously because of its inflammatory nature. In it, Hume raised devastating objections to the claim that the universe showed evidence of purposeful design by an Intelligent Creator. This claim was then widely popular among natural philosophers associated with the Royal Society [[CiteRef::Morris and Brown (2016)]] The ''Dialogues'' is written as a conversation between three characters; ''Cleanthes'', a proponent of the design argument, ''Demea'', a mystic, and ''Philo'', a religious skeptic generally supposed to be Hume's spokesperson. Philo argues that the analogy between the universe and a designed artifact is weak. For example, we experience only one universe and have nothing to compare it to. We recognize human artifacts by contrast with non-artifacts such as rocks. He also notes that we have no experience of the origin of the universe, and that causal inference requires a basis in experienced constant conjunction between two things. For the origin of the universe we have nothing of the sort. ''Demea'' deems ''Cleanthes'' concept of God as cosmic designer to be anthropomorphic and limiting. By the end, Hume's characters' arguments lead the reader to the conclude, with ''Philo'', that God's nature seems inconceivable, incomprehensible, and indefinable and therefore the question of God's existence is rendered meaningless. [[CiteRef::Hume (2007)]][[CiteRef::Oppy (1996)]][[CiteRef::Morris and Brown (2016)]]
|Criticism=Hume's skeptical arguments were troubling to many, and received a good deal of criticism. He was criticized, notably, by a fellow Scottish philosopher of his times; Thomas Reid. [[CiteRef::Fieser (2016)]][[CiteRef::Nichols and Yaffe (2016)]] Reid rejected Hume's theories of perception and causation because of their skeptical consequences. Hume supposed that our perceptual experience was of impressions in our minds. He also maintained that causal relations do not exist in the world, but are rather posited in our minds when two events are constantly conjoined in experience. Such views, taken together made it impossible to claim that our perceptual impressions are caused by objects in an external world. This would require that external objects themselves, and our impressions of them be conjoined in our experience, which is obviously impossible. Hume accepted that his belief in an external world was merely a matter of habit, custom, or instinct, and could not be justified. Reid found this unacceptable, and supposed that our perceptual experience was directly of objects in the world, just as everyday common sense tells us. He noted that such direct experience was no more mysterious than Hume's supposition that we directly experienced impressions in our mind. [[CiteRef::Nichols and Yaffe (2016)]][[CiteRef::Reid (2007)|pp. 1-10]] Descartes, Locke, Berkeley and Hume's supposition that the direct objects of perception were mental entities such as ideas, impressions, sensations, or sense data remained widely popular into the twentieth century, [[CiteRef::Hatfield (2004)]] but had been strongly challenged by the beginning of the twenty first century [[CiteRef::Warren(2005)]][[CiteRef::Thompson (2007)]]. By that time though, the relationship between this problem and that of external world skepticism had been substantially reconfigured. [[CiteRef::Clark (2017)]]
