Logic Games Flashcards
steps to making and using diagrams
read the scenario and the rules
draw out a base
represent each rule in a way that accurately reflects my understanding (a clear and simple representation that needs to save a system that helps you see how the rules come together)
utilize the question stem
the question stems tell you how to think about the problem.
new information will always allow for new inferences
the question will test what is known known versus what isn’t - what must be versus what could be.
if a question asks for an answer that could be true or could be false so work to eliminate all of the incorrect “must be” answers
double check your rule notations
go back and check the written rule once your done diagramming
make sure what you think your notation means matches what it is actually supposed to mean.
“or”
on the lsat, “or” by itself does not exclude the possibility of both.
if both is not a possibility, they will write “but not both”
There are also a lot of situations that naturally exclude the possibility of both.
“if John is selected, fanny will not be”
come into effect when the “trigger” (the if statement) sets them off.
only apply sometimes
John getting selected is the “trigger” that sets this rule in action. It is “sufficient” (enough) to guarantee the result.
Fanny not being selected is the “result” of John getting selected. WE ARE NOT IMPLYING CAUSATION BUT RATHER A RESULTING INFERENCE. If we know John is selected, Fanny will not be.
“if it rains, John will not go to the park”
we must assume all that all conditional statements are meant to be absolutely true
We know that if it rains, John will not go to the park. that is a guarantee. if is a guarantee.
“opposite”
taking the opposite of each part of a conditional statement is NOT VALID on the LSAT.
“reversing”
reversing the elements of the original argument is NOT VALID on the LSAT
contrapositive
wrong answers are always negated or reversed on its own.
however, reversing and negating is ALWAYS going to be right.
Every conditional statement yields an inference that is valid as negated and reduced.
Contrapositives should be thought as basic understanding to every conditional statement.
Contrapositive will always tell us if the result isn’t true, the trigger isn’t true
“and” and “or” compound conditionals
“if a pie has f and g, it just also have j”
in order for the rule to take place, the pie MUST have f and g. only knowing something about f or only knowing something about g does nothing for us - we need to know something about both. if both g and f are in the pie, then it will also have j.
the contrapositive would start with the result not happening. if the pie does not have J in it, then it must not have f, g, or both f and g.
or definitely includes the possibility of both here.
