7 Stupid Thinking Errors You Probably Make

7 Stupid Thinking Errors You Probably Make
The brain isn’t a flawless piece of machinery. Although it is powerful and comes in an easy to carry container, it has it’s weaknesses. A field in psychology which studies these errors, known as biases. Although you can’t upgrade your mental hardware, noticing these biases can clue you into possible mistakes.

How Bias Hurts You

If you were in a canoe, you’d probably want to know about any holes in the boat before you start paddling. Biases can be holes in your reasoning abilities and they can impair your decision making.

Simply noticing these holes isn’t enough; a canoe will fill with water whether you are aware of a hole or not. But by being aware of the holes you can devise methods to patch them up. The entire domain of the scientific method has largely been an effort to overcome the natural inclination towards bias in reasoning.

Biases hurt you in a number of areas:


  • Decision making. A number of biases can distort decision making. The confirmation bias can lead you to discount information that opposes existing theories. Anchoring can throw off negotiations by forcing you to sit around an arbitrary value.
  • Problem solving. Biases can impede your creativity when solving problems. A framing bias can cause you to look at a problem too narrowly. And the illusion of control can cause you to overestimate the amount your actions influence results.
  • Learning. Thinking errors also impact how you learn. The Von Restorff effect can cause you to overemphasize some information compared to the whole. Clustering illusions can also trick you into thinking you’ve learned more than you actually have.

Here are some common thinking errors:

1) Confirmation Bias

The confirmation bias is a tendency to seek information to prove, rather than disprove our theories. The problem arises because often, one piece of false evidence can completely invalidate the otherwise supporting factors.

Consider a study conducted by Peter Cathcart Wason. In the study, Wason showed participants a triplet of numbers (2, 4, 6) and asked them to guess the rule for which the pattern followed. From that, participants could offer test triplets to see if their rule held.


From this starting point, most participants picked specific rules such as “goes up by 2“ or “1x, 2x, 3x.” By only guessing triplets that fit their rule, they didn’t realize the actual rule was “any three ascending numbers.” A simple test triplet of “3, 15, 317“ would have invalidated their theories.

2) Hindsight Bias

Known more commonly under “hindsight is 20/20“ this bias causes people to see past results as appearing more probable than they did initially. This was demonstrated in a study by Paul Lazarsfeld in which he gave participants statements that seemed like common sense. In reality, the opposite of the statements was true.

3) Clustering Illusion

This is the tendency to see patterns where none actually exist. A study conducted by Thomas Gilovich, showed people were easily misled to think patterns existed in random sequences. Although this may be a necessary by product of our ability to detect patterns, it can create problems.


The clustering illusion can result in superstitions and falling for pseudoscience when patterns seem to emerge from entirely random events.

4) Recency Effect

The recency effect is the tendency to give more weight to recent data. Studies have shown participants can more easily remember information at the end of a list than from the middle. The existence of this bias makes it important to gather enough long-term data, so daily up’s and down’s don’t lead to bad decisions.

5) Anchoring Bias

Anchoring is a well-known problem with negotiations. The first person to state a number will usually force the other person to give a new number based on the first. Anchoring happens even when the number is completely random. In one study, participants spun a wheel that either pointed to 15 or 65. They were then asked the number of countries in Africa that belonged to the UN. Even though the number was arbitrary, answers tended to cluster around either 15 or 65.

6) Overconfidence Effect


And you were worried about having too little confidence? Studies have shown that people tend to grossly overestimate their abilities and characteristics from where they should. More than 80% of drivers place themselves in the top 30%.

One study asked participants to answer a difficult question with a range of values to which they were 95% certain the actual answer lay. Despite the fact there was no penalty for extreme uncertainty, less than half of the answers lay within the original margin.

7) Fundamental Attribution Error

Mistaking personality and character traits for differences caused by situations. A classic study demonstrating this had participants rate speakers who were speaking for or against Fidel Castro. Even if the participants were told the position of the speaker was determined by a coin toss, they rated the attitudes of the speaker as being closer to the side they were forced to speak on.

Studies have shown that it is difficult to out-think these cognitive biases. Even when participants in different studies were warned about bias beforehand, this had little impact on their ability to see past them.

What an understanding of biases can do is allow you to design decision making methods and procedures so that biases can be circumvented. Researchers use double-blind studies to prevent bias from contaminating results. Making adjustments to your decision making, problem solving and learning patterns you can try to reduce their effects.

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The Gentle Art of Saying No

The Gentle Art of Saying No


It’s a simple fact that you can never be productive if you take on too many commitments — you simply spread yourself too thin and will not be able to get anything done, at least not well or on time.


But requests for your time are coming in all the time — through phone, email, IM or in person. To stay productive, and minimize stress, you have to learn the Gentle Art of Saying No — an art that many people have problems with.


What’s so hard about saying no? Well, to start with, it can hurt, anger or disappoint the person you’re saying “no” to, and that’s not usually a fun task. Second, if you hope to work with that person in the future, you’ll want to continue to have a good relationship with that person, and saying “no” in the wrong way can jeopardize that.


But it doesn’t have to be difficult or hard on your relationship. Here are the Top 10 tips for learning the Gentle Art of Saying No:

  1. Value your time. Know your commitments, and how valuable your precious time is. Then, when someone asks you to dedicate some of your time to a new commitment, you’ll know that you simply cannot do it. And tell them that: “I just can’t right now … my plate is overloaded as it is.”
  2. Know your priorities. Even if you do have some extra time (which for many of us is rare), is this new commitment really the way you want to spend that time? For myself, I know that more commitments means less time with my wife and kids, who are more important to me than anything.
  3. Practice saying no. Practice makes perfect. Saying “no” as often as you can is a great way to get better at it and more comfortable with saying the word. And sometimes, repeating the word is the only way to get a message through to extremely persistent people. When they keep insisting, just keep saying no. Eventually, they’ll get the message.
  4. Don’t apologize. A common way to start out is “I’m sorry but …” as people think that it sounds more polite. While politeness is important, apologizing just makes it sound weaker. You need to be firm, and unapologetic about guarding your time.
  5. Stop being nice. Again, it’s important to be polite, but being nice by saying yes all the time only hurts you. When you make it easy for people to grab your time (or money), they will continue to do it. But if you erect a wall, they will look for easier targets. Show them that your time is well guarded by being firm and turning down as many requests (that are not on your top priority list) as possible.
  6. Say no to your boss. Sometimes we feel that we have to say yes to our boss — they’re our boss, right? And if we say “no” then we look like we can’t handle the work — at least, that’s the common reasoning. But in fact, it’s the opposite — explain to your boss that by taking on too many commitments, you are weakening your productivity and jeopardizing your existing commitments. If your boss insists that you take on the project, go over your project or task list and ask him/her to re-prioritize, explaining that there’s only so much you can take on at one time.
  7. Pre-empting. It’s often much easier to pre-empt requests than to say “no” to them after the request has been made. If you know that requests are likely to be made, perhaps in a meeting, just say to everyone as soon as you come into the meeting, “Look guys, just to let you know, my week is booked full with some urgent projects and I won’t be able to take on any new requests.”
  8. Get back to you. Instead of providing an answer then and there, it’s often better to tell the person you’ll give their request some thought and get back to them. This will allow you to give it some consideration, and check your commitments and priorities. Then, if you can’t take on the request, simply tell them: “After giving this some thought, and checking my commitments, I won’t be able to accommodate the request at this time.” At least you gave it some consideration.
  9. Maybe later. If this is an option that you’d like to keep open, instead of just shutting the door on the person, it’s often better to just say, “This sounds like an interesting opportunity, but I just don’t have the time at the moment. Perhaps you could check back with me in [give a time frame].” Next time, when they check back with you, you might have some free time on your hands.
  10. It’s not you, it’s me. This classic dating rejection can work in other situations. Don’t be insincere about it, though. Often the person or project is a good one, but it’s just not right for you, at least not at this time. Simply say so — you can compliment the idea, the project, the person, the organization … but say that it’s not the right fit, or it’s not what you’re looking for at this time. Only say this if it’s true — people can sense insincerity.

Featured photo credit: Pexels via


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