Lsat Logical Reasoning Bible (Chapter 6)

Front 1

Conditional Reasoning...

Back 1

...is the broad name given to logical relationships
composed of sufficient and necessary conditions.

Front 2

Sufficient Condition

Back 2

A sufficient condition can be defined as an event or circumstance
whose occurrence indicates that a necessary condition must also occur.

Front 3

Necessary Condition

Back 3

A necessary condition can be defined as an event or circumstance
whose occurrence is required in order for a sufficient condition to
occur.

Front 4

Conditional Statement

Back 4

If (sufficient condition) then (necessary condition):

sufficient ----> necessary

Front 5

Feature # 1 of Conditional Statements

Back 5

The sufficient condition does not make the necessary condition occur.

That is, the sufficient condition does not actively cause the necessary condition to happen. That form of reasoning is known as Causal Reasoning. Instead, in a
conditional statement the occurrence of the sufficient condition is a sign or indicator that the necessary condition will occur, is occurring, or has already occurred.

Front 6

Feature # 2 of Conditional Statements

Back 6

Temporally speaking, either condition can occur first, or the two
conditions can occur at the same time.

Front 7

Feature # 3 of Conditional Statements

Back 7

The conditional relationship stated by the author does not have to
reflect reality.

Front 8

Repeat form:

Back 8

The Repeat form simply restates
the elements in the original order
they appeared. This creates a
valid inference.

Front 9

Mistaken Reversal:

Back 9

A Mistaken Reversal switches the
elements in the sufficient and
necessary conditions, creating a
statement that does not have to
be true.

Front 10

Mistaken Negation:

Back 10

A Mistaken Negation negates both
conditions, creating a statement that
does not have to be true.

Front 11

Contrapositive:

Back 11

( A ----> B ) is equivalent to ( ~B ----> ~A)

When the necessary condition fails to occur, then the sufficient condition cannot occur.

Front 12

Sufficient Condition indicators:

Back 12

If, When, Whenever, Every, All, Any, People who, In order to, The only way to

Front 13

Necessary Condition indicators:

Back 13

Then, Only, Only if, Must, Required, Unless, Except, Until, Without

Front 14

When "unless", "without", "except", "until" appear in a conditional statement...

Back 14

1. Whatever term is modified by “unless,” “except,” “until,” or “without” becomes the necessary condition.

2. The remaining term is negated and becomes the sufficient condition.

Front 15

If

Back 15

Sufficient Condition indicator

Front 16

When

Back 16

Sufficient Condition indicator

Front 17

Whenever

Back 17

Sufficient Condition indicator

Front 18

Every

Back 18

Sufficient Condition indicator

Front 19

All

Back 19

Sufficient Condition indicator

Front 20

Any

Back 20

Sufficient Condition indicator

Front 21

People who

Back 21

Sufficient Condition indicator

Front 22

In order to

Back 22

Sufficient Condition indicator

Front 23

The only way to

Back 23

Sufficient Condition indicator

Front 24

Then

Back 24

Necessary Condition indicator

Front 25

Only

Back 25

Necessary Condition indicator

Front 26

Only if

Back 26

Necessary Condition indicator

Front 27

Must

Back 27

Necessary Condition indicator

Front 28

Requires/d

Back 28

Necessary Condition indicator

Front 29

Unless

Back 29

Necessary Condition indicator

Front 30

Except

Back 30

Necessary Condition indicator

Front 31

Without

Back 31

Necessary Condition indicator

Front 32

Until

Back 32

Necessary Condition indicator