## Presentation on theme: "Wason’s selection task"— Presentation transcript:

E K <- four cards Each card in a deck of cards has a letter on one side and a number on the other Claim: If there is an even number one side, then there is a vowel on the other side

problem and solution E K 4 7
If there is an even number on one side, then there is a vowel on the other side. Determine which cards need to be turned over to verify that the rule or claim holds answer: “4,” “K,” but not “E,” “7” only ~10% of population gets the right answer

another selection problem
You serve drinks in a bar. Every patron of the bar has an age and a beverage. beer water If you are drinking alcohol, then you have to be at least 21 years of age. Which patrons do you need to know more about to see if the law is being observed? Answer: check out 16-year old and the beer drinker; leave others alone most of the population gets the answer right

differences in problems
connection to everyday life EK47 version has no connection to everyday life; whereas, the bar problem does difference in content: abstract version (EK47) and the realistic version (bar version)

logical structure of bar problem
beer water If someone is drinking alcohol, then they must be 21 years or older. “p” = drinking alcohol “q” = being 21 years or older If p, then q

replace content with terms
beer water If p, then q (p = drinking alcohol; q = 21 years or older) 16  “not q” beer  “p” 22  “q” water  “not p”

logical structure not q q p not p If p, then q
exactly the same logical structure with EK47 version

conditions of naturally good critically thinking skills
more likely when we have realistic content in the problem explanation: minds have a natural ability to solve logic problems, but only in situations of realistic content deontic content: situations involving social rules (laws, detecting cheaters, etc.)

Implicit statements If Michael Jackson is a normal guy, then I’m a monkey’s uncle. (I’m not a monkey’s uncle.) (Michael Jackson is not a normal guy.) Implicit = unstated (indicate implicit statements by using parentheses)

logical structure of implicit statements
If Michael Jackson is a normal guy, then I’m a monkey’s uncle. If p, then q (p = MJ normal guy, q = monkey’s uncle) not q (I’m not a monkey’s uncle.) not p (MJ is not a normal guy.)  denial of the consequent (modus tollens)

realistic vs. abstract versions
If p, then q <- alone, no particular implications If MJ is a normal guy, then I’m a monkey’s uncle <- adding words, particular implication is that MJ is not a normal guy

logical operators If…then (conditional)
= if p, then q  under the condition that p is true, q is true not (negation) “~” = not p  p is not true and (conjunction) = p and q  both p and q are true

Disjunction OR (disjunction) = p or q  either p or q is true
logical operators allow you to combine information (premises) into logical statements

Interpretation of disjunction
p OR q  either p or q is true but what about “I am male or female.”  you are one or the other but not both (exclusive OR) excludes both (XOR) what about “I am happy or smart.”  you are one or the other or both (inclusive OR) includes both

Interpretation of OR p or q
could mean, p is true or q is true but not both alternatively, could mean, p is true or q is true or both unless specifically stated, either interpretation is possible

Disjunctive Reasoning
doing reasoning or critical thinking involving the word “or” Start paying attention to me or I’ll kick you out of the class. (p or q) disjunction means, If you don’t pay attention to me, then I’ll kick you out of the class. (If p, then q) conditional