jamie likes to fetch

General Claims and Their Contradictions
Epstein states that “we need to know how to reason using general claims that assert something in a general way about all or a part of a collection. Claims may seem valid but they aren’t.

For example, “All dogs like to play fetch. Jamie likes to play fetch. So Jamie is a dog.”

It seems valid but it’s not. The premises could be true but Jamie could either be a hamster, cat, hedgehog, bird or etc. that likes to play fetch. Dogs aren’t the only animals that like to play fetch. Arguments that sound correct are actually bad.

In order to avoid getting lured into belief we first must understand what “all” and “some” mean. All means “Every single one, no exceptions” or sometimes depending on the argument All could also mean “Every single one, and there is at least one.” Some means “At least one,” or “At least one, but not all,” depending on the argument. This is where contradictions play into the general claims. We use contradictions to counter arguments that we experience on the daily. Contradictions further the discussion.

For example, let’s go back to the state used above about “All dogs like to play fetch,” someone could use it’s contradiction against it, “Not all dogs like to play fetch.”