- The internal manipulation of information, which allow us to draw conclusions and formulate new knowledge.
Rules for Proper Reasoning- so new knowledge we create is logical and sound.
Two types of reasoning-
1. Syllogistic- reasoning based on premises. From the premises, a conclusion is drawn.
P: All boys are athletes.
P: All athletes are muscular
C: All boys are muscular.
- Typically taken to be true even if they do not reflect an empirical reality
o What is the actual state of affairs in the world? NOT really an actual state? for sake of argument
- Typically state relationships between concepts
o What are the concepts being discussed and what are the relationships between them?
o Is the conclusion valid between the two concepts?
How do you decide if you have a valid conclusion? Valid conclusion-
the only conclusion that can be drawn about stated concepts given the relationships
expressed in premises.
- A necessary conclusion
- The only way it can be
- If anything else is possible, it is not valid
- Not just possible, it is necessary
Is the conclusion valid? How to determine:
Analyze by using Venn Diagrams
- Start with premise #1
a.) ? (Put boys on top athletes=all
boys are athletes)
All boys are athletes but not all athletes have to be boys.
- Premise #2
- P: All boys are athletes.
P: All muscular people are athletes
C: All boys are muscular
2. Conditional Reasoning- form of reasoning stated as an “IF…THEN” statement
Ex. If she has red hair, then she buys new shoes.
The IF statement is referred to as the antecedent condition (condition that comes before). The THEN statement is referred to as the consequent. The consequent is assumed to be necessary.
Series of observations- from observations you draw conclusions? validity
1. She has red hair. (obs)
She buys new shoes. (concl)
VALID- affirming the antecedent (AA)
Conclusions based on AA, are true.
2. She has NOT red hair.
She does not buy new shoes.
NOT VALID- denying antecedent (DA)
Conclusions based on DA are not valid.
3. She buys new shoes.
She has red hair.
NOT VALID- affirming consequent (AC)
Conclusions based on AC are not valid.
4. She buys not new shoes.
She does not have red hair.
VALID- denying consequent (DC)
Conclusions based on DC are valid.
Peter Wason- wanted to test how logical people were. Question in “IF…THEN” statement. He presented people with 4 cards- a letter on one side and a number on the other.
If there is a vowel on one side, there is an even number on the other side.
Turn E- AA=Valid Turn 4- AC=Not Valid
Turn K-DA=Not Valid Turn 7-DC=Valid
Problem Solving- any sort of cognitive process directed toward a specific goal, the goal being to achieve a solution to problem or challenge.
- Popular as a research study
- Clearly measured success or failure.
1. Trial and Error- process of engaging in various responses or behaviors and the evaluation of the response or behavior.
2. Algorithms- specific formulas or procedures, if followed properly, guarantee a solution. This only works for well-defined problems (any problem where all the relevant variables are known and are measurable).
- Many real world problems are “ill defined” (where all relevant variables are not known or are not measurable)
3. Heuristics- general strategies for problem solving that tend to work more often than fail
- Not guaranteed
- Better off with, than without
- Rules of thumb
- Commonly used in Problem Solving:
1. Measured analysis- take larger, complicated problems, break it down into smaller, simpler problems (one at a time), in the end, the big one should be solved.
2. Availability heuristic- using what most easily comes to mind as strategy (progress from most simple to complicated).
o Can cause distortions depending on perception
3. Representativeness heuristic- using particular example as representative of entire category
o Can often be successful and efficient
o Can over generalize and distort information
4. Analogies- using past experience of similar type of problem as model for current problem
- Very controversial
- When might past experience be helpful and harmful to problem solving
- Dunker (1995) studied “make a lamp” problem. This is when a group was given a box with supplies in it and was told to use these items to make a lamp. The group used the items inside box and disregarded the box itself. When the second group was handed the box without the supplies in it (with it), they utilized the box along with all materials.
- It was harmful to group 1 because they used the box to hold things, not as a part of the materials.
- If past experience inhibits creativity, it is harmful and called functional fixedness.
- Mental set- persisting in using problem solving strategies that have worked in the past rather than trying new ones.
Gick and Holyoak- 1983 Helpful
Subjects were given same problem
1st group 2nd group 3rd group
Very difficult given past given past experience
10% solved experience unknowingly knowing
20% solved 80% solved