You presented two alternative states as the only possibilities, when in fact more possibilities exist.

Assuming that what is true of the whole is true of its parts.

When you argue that this is the way we always have done it. It shouldn't be relied on because times are changing.

When people jump to conclusions with too little information.

Assuming that the group has the same properties as the individual members of the group.

"How can you make a decision about someone having marital problems if you've never been married yourself?"

“Drink Gatorade because that’s what all the professional athletes do to stay hydrated.”

Ana said, "Don't be so rude to the new girl."

Tina replied, "I can't believe that you'd choose to be friends with the new girl than me who have always known you."

“If I were you, I’d think twice before publishing that article. We’ve had writers who have lost their jobs because they didn’t follow the editorial guidelines.”

Mother said, "It's bedtime Jane."

Jane asked, "Mom, how do ants feed their babies?"

"You can't do that, think of the kids. Do you want to hurt them?"

"Smoking cigarettes can kill you because cigarettes are deadly."

"A number of immigrants settle in a nearby city. The city suffers an economic decline. The immigrants' arrival cause the decline."

We should consider knowing about these fallacies in determining the truth.