David Hume (1711-76)

1. David Hume (1711-76) An Enquiry Concerning Human Understanding

2. An Enquiry Concerning Human Understanding • Section 1: Philosophy • Section II: Origin of Ideas • Section III: Association of Ideas • Section IV: Sceptical Doubts Concerning the Understanding • Section V: Sceptical Solutions of these Doubts • Section VI: Of Probability • Section VII: Of the Idea of Necessary Connection

3. Section 1: Philosophy • The purpose of human beings isreason and action. • Human beings appeal to both reason and sentiments or feelings.

4. Philosophy • Speculations are abstract and unintelligible to common readers. • Easy and obvious philosophy will have preference over the accurate and abstruse for the common person.

5. Common Sense • If you depart from common sense and make a mistake, you will never detect it. • If you stick to common sense and make a mistake, then you will have a standard that will make you aware of your mistake.

6. Common Sense • “It is easy for profound philosophers to commit a mistake in his subtle reasonings; and one mistake is the necessary parent of another, while he pushes on his consequences, and is not deterred from embracing any conclusion, by its unusual appearance (i.e. lacking common sense), or its contradiction to popular opinion” . • “But a philosopher, who purposes only to represent the common sense of mankind in more beautiful and more engaging colors, if by accident he falls into error, goes no farther, but renewing his appeal to common sense, and the natural sentiments of the mind, returns into the right path, and secures himself from any dangerous illusions” .

7. Philosophy and Moderation • The philosopher is remote from mankind. His principles and theories are also remote, and their comprehension equally remote. • The ignorant person or he who is destitute of all understanding of the science and arts is worse than the philosopher. • Most perfect character is some where in between these extremes.

8. Well rounded • Human beings are reasonable. • Human beings are social. • Human beings are active. • A mixed life is the best life. • “Indulge your passion for science, says she [nature], but let your science be human, and such as may have a direct reference to action and society” .

9. Philosophy • “Abstruse thought and profound researches I prohibit, and will severely punish, by the pensive melancholy which they introduce, by the endless uncertainty in which they involve you, and by the cold reception which your pretended discoveries shall meet with, when communicated. Be a philosopher; but, amidst all your philosophy, be still a man”.

10. Philosophy • Accuracy • Reasoning • Must have some practical benefit for all of society.

11. Metaphysics • Source of error and uncertainty. • Not properly a science. • “airy science” • Religious superstition. • Religious fears and prejudices.

12. Undermining Metaphysics • A proper study of the the nature of human understanding is the only way to get rid of abstruse philosophy and metaphysics. • Metaphysics mixed with religious superstition has an air of science but it is not science.

13. Section II: Origin of Ideas • Impressions: are all our lively PERCEPTION. • Thought and Ideas: are the images derived from MEMORY and IMAGINATION. • “The most lively thought is still inferior to the dullest sensation”.

14. Creative Powers of the Mind All ideas are derived from internal or external impressions. • Compounding • Transposing. • Augmenting. • Diminishing.

15. Examples • The idea of God. • A blind person • One exception: The missing shade of blue.

16. Banish the Jargon • What words have meaning? • What are the meaning of words? • Metaphysical reasoning: Abstract ideas are naturally faint and obscure without distinct meaning. • “From what impression is that supposed idea derived?” • “By bringing ideas into so clear a light we may reasonably hope to remove all dispute, which may arise, concerning their nature and reality” .

17. Section III: Association of Ideas • Resemblance • Contiguity in time or place. • Cause and effect.

18. Section IV: Sceptical Doubts Concerning the Understanding 2 Sources of all knowledge • Relations of Ideas • Matters of fact

19. Relations of Ideas • Relations of Ideas: propositions that are discoverable through the operations of the mind alone (i.e. a priori). • Their contrary is a contradiction • For example: mathematical truths, 2+2=4

20. Matters of Facts • Matters of fact: propositions discoverable through experience. • Their contrary is not a contradiction and thus logically possible. • Any empirical fact, “Humans have a heart” The earth is round”

21. Matters of Fact • “The sun will rise tomorrow.” • Opposite: “The sun will not rise tomorrow” is not contradictory and therefore it is a matter of fact.

22. Matters of Fact • What is the evidence for the truth of matters of facts?

23. Matters of Fact • Reasoning concerning all matters of fact are based on Cause and Effect. • What is the evidence for Cause and effect? • All relations of cause and effect are based on EXPERIENCE.

24. Cause and Effect • All cause and effect are based on a posteriori reasoning. • Knowledge of this relation depends entirely on experience. • When we find that particular objects are constantly conjoined with each other we conclude that there is some special connection between these objects (fire and smoke).

25. Cause and Effect • The knowledge of the relationship between cause and effect is not logical or a priori. • A person with all the logical knowledge possible can never know that water will cause suffocation or that fire will consume him, if he has no experience of these objects before hand.

26. Cause and Effect • One billiard ball will communicate motion to another ball. • This fact can be known only through experience. • However, because the fact is so engrained in us from such an early age (it becomes instinctive) we are biased and believe that we could know this fact a priori.

27. Laws of Nature • The laws of natures are general principles that explain particular events. • However, the laws of nature can only be determined through cause and effect and through experience. • There is no a priori reasoning that can help us discern the laws of nature. • The contrary of any law of nature is not contradictory.

28. Cause and Effect • “The mind can never possibly find the effect in the supposed cause, by the most accurate scrutiny and examination. For the effect is totally different from the cause, and consequently can never be discovered in it.” • For instance, motion in one billiard ball is quite distinct act from the motion in the second.

29. Ultimate Principles: Gravity • That the coin I hold in my hand falls to the floor when I drop it is completely arbitrary. It could have done an infinite number of things. • There is no way for me to have determined what the effect was going to be if I had no prior experience of the world.

30. Ultimate Principles • “We can trace up the particular phenomena to, or near to, these general principles” (e.g. gravity) But the ultimate principles (ultimate causes) themselves remain unexplained. • “These ultimate springs and principles are totally shut up from human curiosity and inquiry” .

31. Real Existence • The existence of any object what so ever must also be based on experience.

32. Part II: Matters of Fact What is the nature of reasoning concerning Matters of fact? • Answer: Cause and Effect What is the foundation of our reasoning concerning cause and effect? • Answer: Experience What is the nature of our reasoning concerning all experience? • Answer: Cause and Effect

33. Experience=Knowledge • Experience provides direct and certain information of those objects which are the objects of the experience. • On what basis do I extend my knowledge of experience to the future?

34. The Future • “(a) I have found that such an object has always been attended with such an effect, and (b) I foresee, that other objects, which are, in appearance, similar, will be attended with similar effects” • (b) is always inferred from (a). • But the connection between these propositions are not intuitive.

35. Scepticism about Induction 1) Scepticism about the cause and effect connection in particular events. 2) scepticism about the General Laws based on the evidence of particular events. 3) Scepticism about future events based on the evidence of particular past events.