fallacy

Everyday

1. A fallacy is a false idea that many people believe. tree →
2. In logic, a fallacy is a mistake in reasoning that makes an argument wrong, even if it sounds convincing. tree →

In the lessons

In ethics and logic lessons, pupils learn fallacies like «everyone does it, so it's right» (bandwagon), attacking the person instead of the argument, and the «gambler's fallacy» (thinking after five heads, tails is «due» — in fact each coin toss is still 50-50). Spotting fallacies helps with news and adverts.

Examples

• It is a fallacy that we only use ten percent of our brains. tree →
• «Everyone's doing it» is a fallacy, not a reason. tree →
• The gambler's fallacy fools lots of people. tree →
• She pointed out the fallacy in his argument. tree →
• It's a common fallacy that bats are blind. tree →
• Name-calling instead of answering is a fallacy. tree →

Note

Plural: fallacies. Adjective: fallacious (formal). In maths probability, past coin tosses do not change the next toss.