Construct a deductive argument that is valid but not sound. 

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pohnpei397 | College Teacher | (Level 3) Distinguished Educator

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A deductive argument consists in part of a premise and a conclusion.  These are the parts of the argument that are important for validity and soundness.  A valid argument is one where the conclusion has to be true if the premise is true.  A sound argument is one that is valid and in which the premise is actually true.

Therefore, a deductive argument that is valid but not sound might be:

  • Only teachers have black hair.
  • I have black hair.
  • Therefore, I am a teacher.

This is valid because I would have to be a teacher if my hair is black and only teachers have black hair.  But it is not a sound argument because there are plenty of people who have black hair and are not teachers.  Therefore, the premise of this argument is not actually true.