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Reason the final chapter


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third and last presentation on Reason ass a way of knowing for Theory of Knowledge

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Reason the final chapter

  1. 1. Reason : The final chapter
  2. 2. Fallacies: <ul><li>Recap Fallacies: </li></ul><ul><li>Post hoc ergo propter hoc </li></ul><ul><li>Ad Hominem Fallacy </li></ul><ul><li>Circular reasoning </li></ul><ul><li>Equivocation </li></ul><ul><li>False Dilemma </li></ul><ul><li>More Fallacies! </li></ul><ul><li>Special pleading </li></ul><ul><li>Argument ad ignorantiam </li></ul><ul><li>False Analogy </li></ul><ul><li>Loaded questions </li></ul>
  3. 3. Fallacies <ul><li>Special pleading </li></ul><ul><li>This fallacy involves the use of double Standards . </li></ul><ul><li>The speaker makes an exception in their own case, that would not be found to be acceptable if it came from someone else . Eg: </li></ul><ul><li>Imagine there is a drought and a hosepipe ban. </li></ul><ul><li>“ I know there is a drought and we need to save water, but I am putting my prize flowers in a competition next week and I need to give them plenty of water.” </li></ul><ul><li>He is giving a justification for his behaviour that he would not accept if it were given by someone else. </li></ul>
  4. 5. Fallacies <ul><li>Richard Dawkins </li></ul><ul><li>This fallacy is committed every time a person claims something is true, on the grounds that there is no evidence to disprove it . </li></ul><ul><li>“ There is an infinity of possible things that one might believe – unicorns </li></ul><ul><li>Fairies, millions of things </li></ul><ul><li>- just because you can’t disprove them doesn’t mean there is anything plausible about them.” </li></ul><ul><li>Argument ad ignorantiam </li></ul>
  5. 6. fallacies <ul><li>False Analogy </li></ul><ul><li>In trying to persuade people of something you might use various analogies to support your argument. </li></ul><ul><li>An analogy is a comparison between one thing another which implies that the two are similar in some significant sense . </li></ul><ul><li>This can be an effective rhetorical device </li></ul><ul><li>A false analogy arises when you assume that because two things are similar in some respects they must also be similar in some further respect . </li></ul>
  6. 7. False Analogy <ul><li>This is William Paley. </li></ul><ul><li>Some people think that Paley was guilty of a making false analogy in his Teleological argument for the existence of God. </li></ul><ul><li>Lets see why: </li></ul>
  7. 8. False Analogy <ul><li>Paley compared the universe to a watch. </li></ul><ul><li>He said that because a watch is so intelligently designed, we should assume the existence of a designer, or watchmaker. </li></ul><ul><li>He then said that because the universe also appears to have been intelligently designed, we should infer the existence of a designer here too. </li></ul><ul><li>He said this designer was God. </li></ul>
  8. 9. <ul><li>Some people would argue that the comparison of a watch to the universe is a false analogy. </li></ul><ul><li>This is because the two things are radically different in a number of ways, apart from the fact that they are both complicated to an extent. </li></ul>
  9. 10. fallacies <ul><li>Loaded Questions </li></ul><ul><li>A loaded question is one that contains a built-in assumption that has not been justified and may be false . </li></ul><ul><li>For example, imagine if someone asked you the question.. </li></ul><ul><li>If you answer: </li></ul><ul><li>Then you are admitting that you always cheat. But if you answer: </li></ul><ul><li>Then you are implying that you sometimes cheat . </li></ul><ul><li>What you have to do is challenge the assumption built into the question and say: </li></ul>“ Do you always cheat in exams?” “ Yes” “ No” “ No -I never cheat in exams.”
  10. 11. Reason and certainty
  11. 12. Reason and certainty <ul><li>We have looked at inductive reason, deductive reason. </li></ul><ul><li>The fact that fallacies can arise with both these kinds of reason suggests that we cannot always rely on reason to give us knowledge. </li></ul><ul><li>The conclusions of deductive arguments can be no more certain than the premises they are based on. </li></ul>
  12. 13. <ul><li>In practice then, it seems that at best, reason is a means of preserving truth, only in the sense that if a person starts with truth, and reasons validly, they will also end up with truth. </li></ul><ul><li>However we might say that as a way of thinking, logical reasoning cannot really be doubted. </li></ul><ul><li>This reasoning is based on three laws ... </li></ul>
  13. 14. The three Laws of Thought <ul><li>1) the law of identity </li></ul><ul><ul><li>If A, then A. </li></ul></ul><ul><ul><li>‘ if something is an orange, then it is an orange.’ </li></ul></ul><ul><li>2) the law of non-contradiction </li></ul><ul><ul><li>Nothing can be both A and not A </li></ul></ul><ul><ul><li>“ nothing can be both an orange and not-an-orange </li></ul></ul><ul><li>3) the law of the excluded Middle </li></ul><ul><ul><li>Everything is either A or not A </li></ul></ul><ul><ul><li>‘ everything is either an orange or not an orange.’ </li></ul></ul>
  14. 15. <ul><li>These may seem fairly obvious and irrefutable. </li></ul><ul><li>if you take all the oranges in the universe and put them on your left </li></ul><ul><li>And take all the non-oranges and put them on the right </li></ul><ul><li>There is nothing left in the middle hovering uncertainly between being and not being an orange </li></ul>
  15. 16. An orange with an identity crisis?
  16. 18. “ Why should I be logical? ”
  17. 19. What to say to a person who asks why they should be logical: <ul><li>On one level this question is self-defeating , because in asking for reasons, the person has pre-supposed the value of logic . </li></ul><ul><li>In fact, logic is pre-supposed in all meaningful communication. </li></ul><ul><li>Surely any assertion that P, if it is to make sense, must exclude the proposition not P. </li></ul>
  18. 20. “ we have a love-hate relationship”
  19. 21. Is it possible to both ‘ love ’ and ‘ not love ’ someone? <ul><li>This is true in some ways, but not in a way that undermines logic . </li></ul><ul><li>You cannot love and not love the same person in the same way at the same time. </li></ul><ul><li>What you really mean when you say you are in a ‘love-hate’ relationship, is that you love them in certain ways or at certain times , and hate in certain ways or at certain times. Never both at the same time . </li></ul><ul><li>Cathy and Heathcliff might be said to have a love-hate relationship in Emily Bronte’s story Wuthering Heights </li></ul>
  20. 23. How rational are you? <ul><li>Use your logical skills and lateral thinking to solve the following situations: </li></ul><ul><li>A man walks into a bar and asks for a glass of water. </li></ul><ul><li>The barman pulls out a gun and points it up at the man. </li></ul><ul><li>The man says ‘thank you’ and walks out. </li></ul><ul><li>Solution: </li></ul><ul><li>the man had hiccups </li></ul>
  21. 24. Lateral thinking questions <ul><li>A man is lying dead in a field </li></ul><ul><li>Next to him there is an unopened package. </li></ul><ul><li>There is not other living creature in the field. </li></ul><ul><li>How did he get there? </li></ul><ul><li>Solution: </li></ul><ul><li>The man’s parachute failed to open. </li></ul>
  22. 25. Lateral thinking <ul><li>Anthony and Cleopatra are lying dead on the floor of a villa in Egypt. </li></ul><ul><li>Nearby is a broken bowl. </li></ul><ul><li>There is no mark on either of their bodies and they were not poisoned. </li></ul><ul><li>How did they die? </li></ul><ul><li>Solution: </li></ul><ul><li>Anthony and Cleopatra are goldfish </li></ul>
  23. 26. Evaluating Reason <ul><li>Rene Descartes </li></ul><ul><li>He was a Rationalist Philosopher </li></ul><ul><li>He thought that Reason as a way of knowing could provide us with absolute certainty. </li></ul><ul><li>But we have seen that this is dubious </li></ul><ul><li>because reason is only as certain as the premises on which it is based. </li></ul>
  24. 27. Beware the prison of logic
  25. 28. Evaluating Reason <ul><li>Reason can sometimes become a double-edged tool </li></ul><ul><li>We need to reason to develop consistent beliefs about the world, but can sometimes become trapped in the so called ‘prison of logic’. </li></ul><ul><li>Reason is not appropriate to be used in every situation; </li></ul><ul><li>And if someone is too rational they may simply come across as cold and unfeeling . </li></ul><ul><li>In private life, for example the best way to resolve a dispute with a loved-one may not be by proving their inconsistency to them, </li></ul><ul><li>But by showing them empathy, compassion and understanding. </li></ul>
  26. 29. Essay Question: <ul><li>All knowledge claims should be open to rational criticism. On what grounds and to what extent would you agree with this assertion? </li></ul>
  27. 30. <ul><li>All knowledge claims should be open to rational criticism. On what grounds and to what extent would you agree with this assertion? </li></ul>
  28. 31. Things to consider when writing the essay: <ul><li>Is there any kind of knowledge which is great enough to override reason? </li></ul><ul><li>If so, what is it? when might it occur? and how do we know that it is genuine? </li></ul><ul><li>If not, then how do we know reason is the most reliable form of knowledge? </li></ul>