Evolution of Logical Reasoning

Lindsay Thibodeau

The Four Common Conditional Statement Forms In Logical ReasoningRule: If P then Q (P) (not P) (Q) (not Q)

-Affirming the

Consequent

-Denying the

Antecedent

First premise

P Q Not P Not Q

Conclusion

Q P Not Q Not P

Validity Valid Not Valid

Not Valid

Valid

Wason Selection Task

A X 2 3

P not P Q not Q

Rule If there is a vowel, there is an even number Which card(s) do you flip? Correct answer A 3 Why? If card A does not have a even number on the other side it

disproves the rule. If the 3 card has a vowel an the other side it disproves the rule as well.

General Stucture of the Wason Test

Example of Wason Test with a Social Contract Rule

Borrowed Car

Did not borrow car

Filled up tank with gas

Did not fill up tank with gas

P not P Q not Q

General Structure of a Social Contract Problem

If you take the benefit, then you must satisfy the requirement. (If P then Q )

Benefit Accepted

P

Benefit not accepted

Not P

Requirement satisfied

Q

Requirement not satisfied

Not Q

Two Problems based on the Wason Selection Test

Abstract Difficult Complex

Wason Selection Test

Why are we better at solving logical problems put in social perspective?

Social Easier Simple

Evolutionary Perspective Cheater Detection Theory

Rely on social ties to survive We live in social networks

Help vs punishment Requirement of a social network

Detecting cheaters Especially good at it!!!

Social Problems DO NOT activate logical reasoning… Switched Format

Standard format:"If you give me your watch, I will give you $100".  “If I take the benefit, then I will satisfy the requirement.”  (If P then Q )

Switched format:"If I give you $100, then you give me your watch"“If I satisfy the requirement, then I take the benefit.” (switched

form)(If P then Q )

Why are we better……

Why are we better cont’d…Standard Format Switched Format

Benefit Accepted (she gave me her watch)

P Q

Requirement Not Satisfied (I gave her nothing)

Not Q Not P

Benefit not Accepted (I got no watch from this woman)

Not P Not Q

Requirement Satisfied (I gave this woman $100)

Q P

Correct Cheater Detection Answer (expressed in logical terms)

P & not Q Q & not P

Thank you

Questions/ Comments?????