Therefore, it is false that no wasps are unfriendly insects. It is false that all professors are ignorant fools. Therefore, no professors are ignorant fools. It is false that some muffins are not wholesome foods. Therefore, some muffins are wholesome foods.
All dictionaries are useful books.
Therefore, it is false that no dictionaries are useful books. In some cases validity depends on whether the Aristitelian standpoint can be taken, so use the circled x's when you can certify that the s terms of universal statements exist. Some economists are Marxists. It is false that some people with childless parents are attractive personalities. Therefore, some people with childless parents are not attractive personalities.