This operation can be used by any proposition type to generate a different but equivalent proposition.
What is obversion?
Negating the predicate is this step in the obversion operation.
What is the second step?
This is the number of steps in the conversion operation.
What is one?
These are the only types of propositions for which contraposition produces an equivalent proposition.
What are A and O?
"A" propositions can use these two operations to generate different but equivalent propositions.
What are obversion and contraposition?
This is the first step in the obversion operation.
What is switching (or changing) the quality of the subject?
These are the only types of propositions for which conversion produces an equivalent proposition.
What are E and I?
These are the three steps of contraposition.
What are 1) Obversion 2) Conversion 3) Obversion again?
"E" propositions can use these two operations to generate different but equivalent propositions.
What are obversion and conversion?
In the last step of the obversion operation, you cancel out these.
What are "double-nons"?
This is the first step of the conversion operation.
What is switching the subject and predicate?
This is the contrapositive of "All mammals are hair-producing animals."
What is "All non-hair-producing animals are non-mammals"?
What are conversion and obversion?
This is the obverse of "All dolphins are mammals."
What is "No dolphins are non-mammals"?
This is the converse of "No angels are mortal beings."
What is "No mortal beings are angels"?
This is the contrapositive of "All true ice creams are desserts made with dairy."
What is "All non-desserts-made-with-dairy are non-true-ice creams"?
"O" propositions can use these two operations to generate different but equivalent propositions.
What are contraposition and obversion?
This is the obverse of "Some trees are not non-deciduous."
What is "Some trees are deciduous"?
DAILY DOUBLE
This is the converse of "Some mushrooms are deadly to eat."
What is "Some deadly to eat items are mushrooms"?
This is the contrapositive of "Some lights are not artificial objects."
What is "Some non-artificial objects are not non-lights"?