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“A present is a surprise only if it is not expected” is a stylistic variant of: 

Use the Traditional Square of Opposition Assuming that “Some games are crazy inventions” is false what does it imply about the truth or falsity of “All games are crazy inventions”?

An O statement is a universal negative statement.

The Traditional Square of Opposition: Identify the relation between the two statements: If one wants to pass this class, then they study hard. Some who want to pass do not study hard.

Use the Traditional Square of Opposition If an an I-statement is true then the corresponding O-statement is:

Use the Traditional Square of Opposition Assuming that “All liars are mendacious ones” is true, what does it imply about the truth or falsity of “No liars are mendacious ones”?

Immediate inference: Identify the relationship using the Traditional Square of Opposition. Then indicate whether the inference is valid: It is false that No astronauts are herbivores. It follows that All astronauts are herbivores.

Immediate inference: Identify the relationship using the Traditional Square of Opposition. Then indicate whether the inference is valid:  There are no philosopher kings, so it is false that there are some philosopher kings.

Term complements: rewrite the categorical statement replacing each term with its complement: No people afraid of heights are skydivers    

Immediate inference: Identify the relationship using the Traditional Square of Opposition. Then indicate whether the inference is valid: It is true that Some astronauts are herbivores. It follows that Some astronauts are not herbivores.