Reason the final chapter
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Reason the final chapter



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

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



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Reason the final chapter Presentation Transcript

  • 1. Reason : The final chapter
  • 2. Fallacies:
    • Recap Fallacies:
    • Post hoc ergo propter hoc
    • Ad Hominem Fallacy
    • Circular reasoning
    • Equivocation
    • False Dilemma
    • More Fallacies!
    • Special pleading
    • Argument ad ignorantiam
    • False Analogy
    • Loaded questions
  • 3. Fallacies
    • Special pleading
    • This fallacy involves the use of double Standards .
    • The speaker makes an exception in their own case, that would not be found to be acceptable if it came from someone else . Eg:
    • Imagine there is a drought and a hosepipe ban.
    • “ 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.”
    • He is giving a justification for his behaviour that he would not accept if it were given by someone else.
  • 4.  
  • 5. Fallacies
    • Richard Dawkins
    • This fallacy is committed every time a person claims something is true, on the grounds that there is no evidence to disprove it .
    • “ There is an infinity of possible things that one might believe – unicorns
    • Fairies, millions of things
    • - just because you can’t disprove them doesn’t mean there is anything plausible about them.”
    • Argument ad ignorantiam
  • 6. fallacies
    • False Analogy
    • In trying to persuade people of something you might use various analogies to support your argument.
    • An analogy is a comparison between one thing another which implies that the two are similar in some significant sense .
    • This can be an effective rhetorical device
    • 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 .
  • 7. False Analogy
    • This is William Paley.
    • Some people think that Paley was guilty of a making false analogy in his Teleological argument for the existence of God.
    • Lets see why:
  • 8. False Analogy
    • Paley compared the universe to a watch.
    • He said that because a watch is so intelligently designed, we should assume the existence of a designer, or watchmaker.
    • He then said that because the universe also appears to have been intelligently designed, we should infer the existence of a designer here too.
    • He said this designer was God.
  • 9.
    • Some people would argue that the comparison of a watch to the universe is a false analogy.
    • 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.
  • 10. fallacies
    • Loaded Questions
    • A loaded question is one that contains a built-in assumption that has not been justified and may be false .
    • For example, imagine if someone asked you the question..
    • If you answer:
    • Then you are admitting that you always cheat. But if you answer:
    • Then you are implying that you sometimes cheat .
    • What you have to do is challenge the assumption built into the question and say:
    “ Do you always cheat in exams?” “ Yes” “ No” “ No -I never cheat in exams.”
  • 11. Reason and certainty
  • 12. Reason and certainty
    • We have looked at inductive reason, deductive reason.
    • The fact that fallacies can arise with both these kinds of reason suggests that we cannot always rely on reason to give us knowledge.
    • The conclusions of deductive arguments can be no more certain than the premises they are based on.
  • 13.
    • 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.
    • However we might say that as a way of thinking, logical reasoning cannot really be doubted.
    • This reasoning is based on three laws ...
  • 14. The three Laws of Thought
    • 1) the law of identity
      • If A, then A.
      • ‘ if something is an orange, then it is an orange.’
    • 2) the law of non-contradiction
      • Nothing can be both A and not A
      • “ nothing can be both an orange and not-an-orange
    • 3) the law of the excluded Middle
      • Everything is either A or not A
      • ‘ everything is either an orange or not an orange.’
  • 15.
    • These may seem fairly obvious and irrefutable.
    • if you take all the oranges in the universe and put them on your left
    • And take all the non-oranges and put them on the right
    • There is nothing left in the middle hovering uncertainly between being and not being an orange
  • 16. An orange with an identity crisis?
  • 17.  
  • 18. “ Why should I be logical? ”
  • 19. What to say to a person who asks why they should be logical:
    • On one level this question is self-defeating , because in asking for reasons, the person has pre-supposed the value of logic .
    • In fact, logic is pre-supposed in all meaningful communication.
    • Surely any assertion that P, if it is to make sense, must exclude the proposition not P.
  • 20. “ we have a love-hate relationship”
  • 21. Is it possible to both ‘ love ’ and ‘ not love ’ someone?
    • This is true in some ways, but not in a way that undermines logic .
    • You cannot love and not love the same person in the same way at the same time.
    • 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 .
    • Cathy and Heathcliff might be said to have a love-hate relationship in Emily Bronte’s story Wuthering Heights
  • 22.  
  • 23. How rational are you?
    • Use your logical skills and lateral thinking to solve the following situations:
    • A man walks into a bar and asks for a glass of water.
    • The barman pulls out a gun and points it up at the man.
    • The man says ‘thank you’ and walks out.
    • Solution:
    • the man had hiccups
  • 24. Lateral thinking questions
    • A man is lying dead in a field
    • Next to him there is an unopened package.
    • There is not other living creature in the field.
    • How did he get there?
    • Solution:
    • The man’s parachute failed to open.
  • 25. Lateral thinking
    • Anthony and Cleopatra are lying dead on the floor of a villa in Egypt.
    • Nearby is a broken bowl.
    • There is no mark on either of their bodies and they were not poisoned.
    • How did they die?
    • Solution:
    • Anthony and Cleopatra are goldfish
  • 26. Evaluating Reason
    • Rene Descartes
    • He was a Rationalist Philosopher
    • He thought that Reason as a way of knowing could provide us with absolute certainty.
    • But we have seen that this is dubious
    • because reason is only as certain as the premises on which it is based.
  • 27. Beware the prison of logic
  • 28. Evaluating Reason
    • Reason can sometimes become a double-edged tool
    • We need to reason to develop consistent beliefs about the world, but can sometimes become trapped in the so called ‘prison of logic’.
    • Reason is not appropriate to be used in every situation;
    • And if someone is too rational they may simply come across as cold and unfeeling .
    • 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,
    • But by showing them empathy, compassion and understanding.
  • 29. Essay Question:
    • All knowledge claims should be open to rational criticism. On what grounds and to what extent would you agree with this assertion?
  • 30.
    • All knowledge claims should be open to rational criticism. On what grounds and to what extent would you agree with this assertion?
  • 31. Things to consider when writing the essay:
    • Is there any kind of knowledge which is great enough to override reason?
    • If so, what is it? when might it occur? and how do we know that it is genuine?
    • If not, then how do we know reason is the most reliable form of knowledge?
  • 32.