 Less than 5% of people can solve the following riddle. You are shown 4 cards on a table. For each card, one side has a number and the other side is coloured. Below the cards is a rule. If a card has an even number on one side, it must be red on the other. Now, one of these cards breaks this rule and your job is to fish it out. You can turn over any card you want, but if you choose a card which doesn't need to be inverted, this will count as a fail. Which card slash cards must you turn over? Pause the video now to think about it. The correct answer is to turn over the 8 and the blue card. Remember, the rule was, if the card was even on one side, it must have a red dot on the other. Since the rule is only about even numbers, we don't need to worry about cards with odd numbers. Now, a common mistake is to choose the red card. But, if you turn over the red card and it has an odd number, this doesn't actually break the rule. The rule was only if a card was even, did it have to be red? So, you need to check the 8 to make sure it's red and you need to check the blue card to make sure there's not an even number on the other side. This might be a little confusing. But, what's interesting about this riddle is that there are many variations and some are much easier to get than others. For example, try this one. You are given 4 cards again. By this time, the 4 cards represents 4 people drinking at a party. One side has a person's age and the other side has their drink. The rule is, if you're under 18, you are not allowed to drink alcohol. So, which cards should you turn over? Pause now to think about it. The correct answer is 16 and alcohol. Once again, we don't really care about the 41 year old or the person drinking apple juice. All we care about is whether the 16 year old is drinking alcohol and if the person holding vodka is older than 18. People tend to be better at this version, but why? The logic behind it is the exact same. One theory is that humans didn't evolve to solve logical problems in the cold hard way of the first problem. Instead, we are social creatures and as such, are much better at solving problems in a social context. So, how did you go with these riddles? Also, if you're a content creator, it's probably not likely that you've evolved to track all of your work online. Copypants.com tracks your images and helps you engage positively with the people using your work. They're the sponsors of this video, so check them out. It's free to sign up and you can get $30 of in-app credits when you register with the code P2G.