Did you know:

• A occurs in correlation with B
• -> Therefore, A causes B (or B causes A).

Example: The number of people watching this page is growing everyday; the number of old people in some parts of the World is growing everyday too.
Therefore the number of people watching this page are mostllikely old people.
:-)

This example is easy (even if I'm not sure myself) but in too many cases this logical fallacy might be not be suspected.

Where do I want to come is to remember myself this often used sentence:

Following are some examples correlation and causality logical fallacy:

• "Passive smoking dents children's IQ."
• "People who sleep 6 hours a night live longer then eight or more."
• "People who are married are happier than people who are not."
• "People who own red cars are twice as likely to have an accident as people who own blue cars."
• "Men who have beards are happier than men who do not."

Even:

• "Smoking causes lung cancer" might be a correlation/causality logical fallacy.

So, after visiting this website if your life starts to become better, it might be not because of your visit.


For more info, following are some sources:
cambridge2000.com
statistics-help-online.com
Wikipedia: Correlation does not imply causality