and let the clause “when we hold him under water for sixty seconds he will
not drown“ be denoted by ~D. Then the argument can be symbolized as
I——>~D
~D
Therefore， I
Notice that this argument is fallacious： the conclusion “he is innocent” is
also a premise of the argument. Hence the argument is circular——it proves wh
at was already assumed. The argument affirms the conclusion then invalidly u
ses it to deduce the premise. The answer will likewise be fallacious.
We start with answer-choice （A）。 The sentence
“To insure that the remaining wetlands survive， they must be protected by th
e government“
contains an embedded if-then statement：
“If the remaining wetlands are to survive， then they must be protected by th
e government.“
This can be symbolized as S——>P. Next， the sentence “This particular wetland
is being neglected“ can be symbolized as ~P. Finally， the sentence ”It will
soon perish“ can be symbolized as ~S. Using these symbols to translate the
argument gives the following diagram：
S——>P
~P
Therefore， ~S
The diagram clearly shows that this argument does not have the same structur
e as the given argument. In fact， it is a valid argument by contraposition.
Turning to （B）， we reword the statement “when I eat nuts， I break out in hiv
es“ as
责任编辑：sealion1986
