CONDITIONAL REASONING Flashcards
Sufficient Indicators
If, when(ever), any(time), all, every(time), in order to, people who, each
Necessary Indicators
Then, must, necessary, required, only (if), depends, need (to), have to, essential, precondition
And/Or
To diagram AND/OR Use + for AND
Write our OR to diagram OR
Contrapositive of AND/OR
Always switch the AND/OR when taking the contrapositive of a conditional
NEITHER/NOR
Translates to not this and not that. Diagram as and and conditional
IF and ONLY IF
If and only if is a double indicator. Must be diagramed with a double must arrow <->
Whenever there is an if and only if conditional statement you can switch who is in on the left and right
IF AND ONLY IF FAMILY
If but only if, all and only, but not otherwise, when and only when
EITHER/OR
Inclusion indicator because it forces us to include at least one option. It implies that you must have at least one of the pair
EITHER/OR (Diagramming)
- Negate one half of the statement and put it in the
sufficient condition - Place the other half of the statement in the necessary condition
EITHER/OR (Diagramming Example)
Q: Either I will stare into the distance, or I will make progress
/stare —> progress
NO, NONE, NOBODY, NEVER
Exclusion means you’re going to have to choose between the two variables introduced in the statement. You can’t have both. If the have one of them , you can’t have the other. Rephrasing mutual exclusivity as an if/then statement is essential
NO/NONE (Diagramming)
None of the pocket squares will surrender
Pocket squares —> /surrender
1. Choose one side of the statement and put it in the sufficient condition
2. Negate the other side and put it the necessary condition
UNLESS, EXCEPT, UNTIL, WITHOUT
Conditional exception indicator
Rule: If I go avast the way things always are, I must have my unless exception
UNLESS (Diagramming)
- The target of unless is the exception. Put in the necessary condition
- The other half of the statement is the way things are. Go against the grain. Negate the way things are and put it in the sufficient.
- /[THE WAY THINGS ARE] —> EXCEPTION
SOME, MOST, FEW, MANY, AT LEAST ONE, SEVERAL
Some:
means any quantity of one or more
Most: any quantity in the majority
When diagramming SOME and MOST they always go right before their target , and their target goes straight to the sufficient condition
Ex: “some henchman” = henchman in sufficient condition = henchman <-S>
Ex: “most inkwells” = inkwells in the sufficient condition = inkwells -> (Most arrow)
NOT ALL
Fancy some
