David Hume – Scottish philosopher – 1711-1776. Epistemological approach set out in two key works: A Treatise of Human Nature (1739-1740), Enquiry concerning Human Understanding (1748)
Key issues Hume’s view that our senses provide the raw materials of thought and knowledge – impressions and ideas. ‘Hume’s Fork’ and the attack on Rationalism. Humean account of causation – the central and fundamental type of inference we employ when investigating and thinking about the world. Constant conjunction and Humean ‘projectivism’. The problem of induction.
EMPIRICISM – HUMEAN MOTIVATIONS All knowledge begins with impressions: the deliverances of the senses. Find me an idea that does not originate in experience. People lacking either a sensory modality (e.g. taste) or impressions (e.g. tastes of wine) cannot form ideas of these things. Our mind makes ideas: faint copies of impressions that enable us to think off-line. David Hume (1711-1776) Proof ? Impressions ‘enter with the most force and violence’ or are more ‘vivacious’ than ideas Hume’s Copy Principle: “All our simple ideas in their first appearance are derived from simple impressions, which are correspondent to them, and which they exactly represent”
EMPIRICISM – HUMEAN MOTIVATIONS What about necessary truths? And metaphysical concepts of God and cause and self? Matter of fact = synthetic and contingent truth. “Bernard is a bachelor” The idea of being a bachelor is no part of the idea of Bernard. It’s just a fact about Bernard that he is a bachelor. The books of metaphysics should be “consigned to the flames” Hume’s Fork: Any truth is either a “relation of ideas” or “a matter of fact” There are no substantial (interesting, metaphysical) a priori knowable truths. But what about important metaphysical truths such as “God exists”? “Every event has a cause”? Either they are mere truths of definition or they are, if true, only contingently so. Relation of ideas = analytic and necessary truth. “All bachelors are unmarried” The idea of unmarried is analytically part of the idea of a bachelor. I can conceive of an uncaused event, so it is not necessarily true – not even by definition – that every event has a cause.
Hume’s Fork NecessaryContingent A priori Bachelors are unmarried 2+2=4 RELATIONS OF IDEAS (Analytic truths) ?? A posteriori?? Bob is a bachelor The sun is at the centre of the solar system MATTERS OF FACT (Synthetic truths)
HUME AND CAUSATION Rationalists say that the concept of cause is an innate concept and that we live in a world where nothing happens without a cause. Suppose that a brick is thrown at a window and it breaks. We say that the thrown brick caused the broken window. The concept of cause is learned from experience. Furthermore, there’s no real relation of causation out there in the world. Causation is a psychological relation between impressions/ideas. But does it follow logically from the description of the first event – the thrown brick – that the second event – the broken window – would follow? No! What’s a necessary connexion? How can experience discover this? So, what does it mean to say that one thing causes another? X causes Y = (i) X and Y are spatiotemporally contiguous. (ii) X comes before Y (iii) There is a necessary connexion between cause and effect. So reason cannot discover causal connections. We get the idea of a necessary connexion from seeing X and Y together many times. So, causation boils down to the expectation that Y will follow X. Necessity is psychological not metaphysical.
Fill in the gaps – ‘Hume’s motivations’ and ‘Hume, causation and induction’. Consider why Hume says what he does. Make a note of any difficulties you think he might face Sources - the video worksheet, Ch. 9, Reason and Experience booklet, Grayling handout. Bonus points if you can fill in the blanks about Pavlov…
Bonus points – Pavlov’s Dogs Pavlov - stimulus-response model of explanation When dogs fed a bell was rung. The food (alone) sufficient to make the dogs salivate (unconditioned response). After a while the ringing of the bell alone causes the dogs to salivate. The conditioning history – habit – of the dogs determines their response to the environment. Basis for explanation and prediction.
Further reading and Homework On Billiard Balls – Hume Against The Mechanists – RJP Issue 3 http://www.richmond-philosophy.net/rjp/back_issues/rjp3_hill.pdf http://www.richmond-philosophy.net/rjp/back_issues/rjp3_hill.pdf For Thurs – (1) make you’ve finished the Locke work – and (2) Read the handout. For Thurs – (1) make sure you’ve finished the Locke work – Explain and describe one criticism of innate ideas and (2) Read the Hume and Empricism handout. For next Mon - For next Mon - Explain with an example why the Humean account of causation challenges Rationalism.