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Mathematical Fundamentals


This quiz has a series of truths mixed with fallacies. For each problem, the validity or invalidity is determined solely by the statements given.

We are judging the validity of the "therefore" statement, which claims a particular statement is always correct. It may still be possible the conclusion is true but there isn't enough information to justify it, meaning the argument is invalid.

All planes have wings.

Therefore, all things with wings are planes.


All Bigfoots are monsters.

All monsters are scary.

Therefore, all Bigfoots are scary.


All bees are busy.

No slow things are busy.

Therefore, no slow things are bees.


All aliens are interstellar.

No interstellar things are six-fingered.

Therefore, some six-fingered things are aliens.


All knights are brave.

All skilled people have done practice.

Therefore, some knights have done practice.


No rivers are dry.

No dry things are frogs.

Therefore, no frogs are rivers.


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