Question

Question: Identify the rule that is broken by any of the following syllogisms that are invalid. and name the fallacy they contain.

1.      Some foods that contain iron are toxic substances, for all fish containing mercury are foods that contain iron, and all fish containing mercury are toxic substances.

2.      No writers of led and sensational articles are honest and decent citizens, but some journalists are not writers of lewd and sensational articles; consequently, some journalists are honest and decent citizens. 

3.      All supporters of popular government are democrats, so all supporters of popular government are opponents of the Republican Party, inasmuch as all Democrats are opponents of the Republican Party

4.      No coal-tar derivatives are nourishing foods, because all artificial dyes are coal-tar derivatives, and no artificial dyes are nourishing foods.

5.      No coal-tar derivatives are nourishing foods, because no coal-tar derivatives are natural grain products, and all-natural grain products are nourishing foods.