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Transcript of Reason
Poor Reasons and Logical Fallacies
What is formal reasoning?
Every existing thing is born without reason, prolongs itself out of weakness, and dies by chance.
Reason knowledge issues and links with other WOKs and AOKs
1)Is reason purely objective and universal, or does it vary across cultures? Is logic purely objective and universal?
2)What is the relationship between reason as a way of knowing and logic in its different forms (inductive, deductive, intuitive, natural)? Is it possible and worthwhile to “translate” everyday arguments into formal logical structure, and what might be lost in the translation?
3)What possibilities for knowledge are created by reason? What are the advantages of being able to reason about something rather than, say, feeling something, dreaming about something, wishing something to be the case?
4)Does all knowledge require some kind of rational basis?
There are many ways we ‘use’ reason, and, for that matter, use the term.
These prices are very reasonable
She acted reasonably
He used reason to win the argument
There was no reason why she did that
He had his own reasons for his decision
So then how do we define logic?
How do these terms differ?
The term differs slightly in all these statements, suggesting that reason isn’t always used in the same way. Obviously, reason is something that we use whenever we make a decision, and most of the time, our reasoning occurs instinctively, as we decide on the best path to take almost unconsciously, depending on previous experiences involving similar situations.
It is possible to train ourselves to reason consciously, though, and the more one thinks about the decisions one is making, the more one is able to have active control over them. Some people have termed this intellectual enlightenment, the point where we are consciously aware of every choice we ever make. The extent to which this is achieved determines how rational we are.
The etymology of the word ‘reason’ will help us to decide on the boundaries of how we use it. It is, after all, another one of those words (that somehow we keep bumping into in TOK ) that can mean a lot of different things. The word is derived from the French raison, which itself comes from the Latin, ratio. This word is a translation from the Greek word logos. It’s not easy to define logos. It is one of those words that refuses to be translated, and is better understood as a concept rather than a mere word. For the early Greek philosophers it meant the order of the universe or rational discussion.
The present OED definition of reason is:
• noun 1 a cause, explanation, or justification. 2 good or obvious cause to do something: we have reason to celebrate. 3 the power of the mind to think, understand, and form judgements logically. 4 (one’s reason) one’s sanity. 5 what is right, practical, or possible: I’ll answer anything, within reason.
• verb 1 think, understand, and form judgements logically. 2 (reason out) find a solution (to a problem) by considering possible options. 3 (reason with) persuade with rational argument.
— PHRASES by reason of formal because of. listen to reason be persuaded to act sensibly. it stands to reason it is obvious or logical.
Questions for class discussion:
1. how do we reason?
2. What relationship does it have with emotion? 3. To what extent can we trust decisions that have been made using reasons?
4. What are the fallacies that can arise when reason is not used properly?
Logic: The most ‘formal’ or ‘strict’ type of reason is usually termed logic. Logic is sometimes used instead of the word reason, but if you substitute it in the sentences above, you will see that it makes the sense of the statement much narrower. For something to make logical sense is a more demanding achievement than for something to make reasonable sense. The use of logic to arrive at an answer implies that that answer will be more measurably correct or not.
For our purposes, let’s define logic as the use of reason according to strict rules to help us determine knowledge. (Remember our definition of knowledge, after Socrates: justifiable true belief.) Logic, therefore, becomes our tool for searching out answers and weighing up conflicting statements, opinions, and ideas. It does so in a range of ways, according to the way in which it uses reason. Some of these ways are tried, tested and accepted; others are lessons in how not to use reason.
The most important way of dividing up logic is into deductive and inductive reasoning. Deduction leads to specific conclusions based on weighing up general principles. Induction is the opposite, and produces a general conclusion from a specific case or cases. Each one can be subdivided into further forms and types.
How can we tell the difference between inductive and deductive reason?
Give examples from your subject areas?
Deductive and Inductive Reasoning:
If I am observing a person kicking a football up into the air, and I watch what happens a dozen times, I can logically deduct that on the thirteenth occasion, according to what I have seen, and according to other observations I have made involving people kicking balls into the air, that the football will, after being kicked upwards, fall back to earth. I have arrived, in other words, from a general principle, in this case, gravity, to a specific conclusion: the person I am watching with this particular ball.
Deduction is used by scientists who take a general scientific law and apply it to a certain case, as they assume that the law is true. Deduction can also be used to test an induction by applying it elsewhere, although in this case the initial theory is assumed to be true only temporarily.
Lets look at an example
These involve simple premises, but it also works when you construct a compound premise.
Primary premise: If IB students want to pass their diploma, then they must now pass the TOK course.
Secondary premise: Gabriel wants to pass the Diploma.
Conclusion: Gabriel must pass the TOK course.
We use induction more often than we use deduction in every day life, because unless we are professional scientists, we simply don’t have time to investigate phenomena by repeating experiments to check that our theories work. In other words, we make generalizations on previous experiences, and those previous experiences are often just based on seeing or feeling a thing once or twice.
Probably the best known, and most widely-used form of deductive reasoning is the syllogism. In a syllogism, a primary premise is linked to a secondary premise to arrive at a conclusion. This sounds complicated, but is more easily understood by looking at an example. One that is often cited is:
Primary premise: All humans are mortal.
Secondary premise: Socrates is human.
Conclusion: Socrates is mortal.
This argument is sound because if the two propositions are true, there is no possible way that the conclusion could be false. Another example, slightly more immediate to us, could be:
Primary premise: All IB students must study TOK .
Secondary premise: Gabriel is an IB student.
Conclusion: Gabriel studies TOK .
Description: Inductive reasoning, or induction, is reasoning from a specific case or cases and deriving a general rule. It draws inferences from observations in order to make generalizations.
Inference can be done in four stages:
Observation: collect facts, without bias.
Analysis: classify the facts, identifying patterns o of regularity.
Inference: From the patterns, infer generalizations about the relations between the facts.
Confirmation: Testing the inference through further observation.
In an argument, you might:
Derive a general rule in an accepted area and then apply the rule in the area where you want the person to behave.
Give them lots of detail, then explain what it all means.
Talk about the benefits of the parts and only get to the overall benefits later.
Take what has happened and give a plausible explanation for why it has happened.
Inductive arguments can include:
Part-to-whole: where the whole is assumed to be like individual parts (only bigger).
Extrapolations: where areas beyond the area of study are assumed to be like the studied area.
Predictions: where the future is assumed to be like the past.
What is poor reasoning or a logical fallacy?
A fallacy is a failure in reasoning that leads to an argument being invalid. They are like cracks in the foundation of a building: if they are present, the building is going to fall down. So detecting fallacies is a very important part of making yourself critically skilled: if you know what fallacies are, you can both avoid making them yourself when you present an argument, and spot them when others are using them.
And use them they do. Everyday, you will probably come across dozens of fallacies. Some are present innocently – someone using a line of reasoning that is incorrect by accident. But some are far from innocent, and are deliberately employed to lead us astray. The advertising industry, politics, the media, law – in all of these areas of life, fallacies are used and abused, and more often than not, remain undetected by an audience that ends up tricked and misled.
So learning what fallacies are, and being able to identify them will help you hugely when you get into any kind of debate with other people, in school, and outside of it.
They fall into two categories – formal fallacies (sometimes called logical fallacies), which are fallacies because of the way they are incorrectly structured logically, and informal fallacies, because the meaning of the words and what they express has been used incorrectly.
An example of these two types of fallacies could be:
A formal fallacy:
Some IB students study History
John is an IB student
Therefore, John is studying History
This is a fallacy because although we can say that it is possible that john is studying History, we cannot say that with certainty, because only some IB students study History. Therefore, there is a problem with the logic of the structure.
Write your own example.
An informal fallacy:
TOK teaches people how to argue
People argue all the time
Therefore, people don’t need to study TOK
This is a fallacy, because the meaning the word ‘argue’ is different in the first and second line, so the argument is built on an incorrect meaning.
However, the difference between the two categories is often so fine that is extremely hard to tell when a fallacy is formal or informal. For that reason, it’s more useful to simply learn different examples of the most common fallacies, to enable you to identify them when you come across them. Many of them you will already have come across, but perhaps you have never known they had a name.
Lets go to the circular window and see other types of fallacies
A type of red herring, an ad hominem fallacy is when one of the arguers begins to attack an aspect of the other person’s character involved in the discussion, and uses that as evidence for his lack of ability to make his point.
Example: Attacking a politician for the school where he sends his children.......
Post hoc ergo propter hoc (‘after this, therefore because of this’)
This mistakenly links two or more unconnected events by proposing that one is the cause of the others occurring.
Argumentum ad populum (‘appeal to the people’)
This is an argument that bases its truth on the fact that many people believe that to be the case. It is related to the rather unreliable consensus truth test.
The gambler’s fallacy is the belief that because a random event has happened frequently before, it has less chance of occurring in the future. The reverse gambler’s fallacy is to assume that because something has happened frequently, it will carry on doing so.
Appeals to emotions come in many forms, and involve using a form of emotion such as fear (terrorem), pity, flattery, and so on, to advance an argument. Because they rely on something that is irrelevant to the point of discussion, they are another type of red herring.
One of the worst mistakes to make in history is to look back on an event and assume that those at the time had access to the same knowledge that we do about that event. This is also known as ‘using hindsight’.
Example: Saying that Chamberlain’s policy of appeasement was a terrible mistake - because it was obvious that Hitler was never going to stop expanding, and invade Poland - is a fallacy, because Chamberlain did not have that information available to him at that time.
A slippery slope fallacy is when the person presenting their argument tries to strengthen it by talking about a catastrophic series of consequences occurring as a result of something they are opposed to.
There are many fallacious ways in which comparisons are made to arrive at a conclusion. Inconsistent comparisons are when different elements of two or more objects or phenomena are compared, in order to arrive at a statement about one of them.
This is when the authority or status of a person is used to support an argument. This fallacy is a one of the main features of the advertising industry, with the appeal of products they promote depending on its power.
5)If knowledge claims cannot be rationally defended, should they be renounced? Is the answer to this question dependent on the area of knowledge of the claim?
6)Can reason on its own, independent of sense perception, emotion and language, ever give us knowledge? Or are reason and language inseparable in the quest for, construction and justification of knowledge?
7)How can beliefs affect our capacity to reason well and to recognize valid arguments? Can they affect a person’s capacity to distinguish between fallacy, good argument and rationalization?
8)What, if any, are the advantages of expressing arguments in symbolic terms? Are the ambiguity and vagueness of conventional language eliminated by this formulation?
Why are fallacies often plausible and convincing? Are there circumstances under which the use of informal fallacies can be justified, for example, in public advertising campaigns aimed at persuading us to donate money for good causes (for example, humanitarian relief, children’s funds)?
Description of Straw Man
The Straw Man fallacy is committed when a person simply ignores a person's actual position and substitutes a distorted, exaggerated or misrepresented version of that position. This sort of "reasoning" has the following pattern:
Person A has position X.
Person B presents position Y (which is a distorted version of X).
Person B attacks position Y.
Therefore X is false/incorrect/flawed.