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Avoid stupid decisions: most common cognitive biases and logical fallacies

How can you improve your decision making skills? Webinar recording on exactly that topic.

Bruno Pešec
Bruno Pešec
33 min read
Avoid stupid decisions: most common cognitive biases and logical fallacies

How can you improve your decision making skills?

Logical fallacies are mistakes and flaws in reasoning.

Cognitive biases are cases when we consistently see the reality differently than it objectively is.

These fallacies and biases can interfere with our sense-making and interpretation of what's happening around us, leading us to make bad decisions.

Being aware of them is a valuable step towards improving your thinking and decision making muscles.

Above were the topic of the Avoid stupid decisions: most common cognitive biases and logical fallacies webinar. In 58 minutes I covered:

  • What are stupid decisions and their sources
  • Ten logical fallacies
    • Strawman
    • Loaded question
    • Burden of proof
    • Ad hominem
    • Tu qouque (appeal to hypocrisy)
    • Gambler's fallacy
    • Ambiguity
    • Special pleading
    • Appeal to authority
    • Fallacy fallacy
  • Ten cognitive biases
    • Groupthink
    • Confrimation bias
    • Anchoring
    • Dunning-Kruger effect
    • In-group bias
    • Fundamental attribution error
    • Curse of knowledge
    • Optimism bias
    • Pessimism bias
    • Sunk cost fallacy
  • Four ways to immediately improve your decision making
  • Question from the audience

You can find recording, timestamps, and transcript below.

License information is included at the end.

This webinar was a part Stay home, keep growing series of online events.

Webinar recording

Download link.

Webinar timestamps

Time Topic
01:57 Stupid decisions defined
02:34 Sources of stupid decisions
03:11 Logical fallacies
16:48 Cognitive biases
36:00 Better decisions
42:05 Q&A

Webinar transcript

Hello. Welcome to this webinar. I’ll be your host for I would like to say the night, but it looks pretty sunny here in Oslo. So, this event is part of a broader set of events; all with the intention of keeping you home and help you grow, develop some new skills, some new thinking and hopefully some new approaches as well. I will be focusing today on better thinking and actually even more precisely, avoiding what I call stupid decisions.

Now, before we move in, just a reminder that we’re on Zoom. At the bottom of your screen you should have a Q&A box. So, in there during the speech you can put in some questions and if we have some time, I will answer them by the end. Let’s go.

So, here we can enjoy a bigger picture of myself instead of a small box of me going live; speaking to you, but joking aside. So, before I move in, I just want to say a few words about myself so you can have an anchoring kind of where I come from with my comments.

I am by background an engineer and I used to design battle tanks, weapon systems, freight trains and what not and then I moved more into let’s say innovative space and kind of coming up with new business models with let’s say less than ideally performing products.

In addition to that, I have been working a lot with start-ups. I have mentored and coached several hundreds of start-ups and I keep doing that through various activities and like Founder Institute and Norwegian Lean Startup Circle.

So, kind of I combine this engineering and business view on a lot of things. That’s kind of what lead me to this I don’t want to say obsession, but thinking how to think better.

So, the cornerstone of a stupid decision is being uninformed and drawing wrong conclusions. We cannot actually measure a decision on an outcome because sometimes you might do the right decision with everything you know and the outcome might still be less than ideal. Also, sometimes you might see, I don’t want to say stupid people, but perhaps less than gifted people making stupid decisions with spectacular outcomes. So, it’s like, “How is that possible?” What is the connection here?

Well, the source of stupid decisions is kind of in here. How our brain works and how we connect things around us. I usually like to talk about two things and separate them and so one is logical fallacy and that is basically wrong conclusions based on evidence and assumptions and propositions that we have in front of us and cognitive bias is more about our brain miss-constructing reality. It’s maybe a lot of fancy talk, but as we go through the cases and examples, you will see more and more what it is.

So, starting with logical fallacies. As I said, a logical fallacy is connecting and drawing wrong conclusions based on the evidence, assumptions and propositions that you had before. I will now share ten of them; for the sake of time, ten of them. Let’s say that I experience most commonly within product management context. So, for today, all the framing is going to be around product management. These fallacies and biases appear anywhere and everywhere, but for today this is the focus.

So, first one: it’s not he most common one, but I decided to start with this one because I really wanted to start with a huge bale of hay; the strawman fallacy. It happens when actually people deconstruct what you told them and extract from that something that they feel they can attack. So, for example you might be presenting a road map and someone might pull out a specific feature, presented differently and ask you to defend that. So, that is a strawman. Kind of extracting the main point and throwing it away and reconstructing something that’s much easier to attack. If that happens to you just bring it back. Just repeat, “That is not my main argument. What you now presented back is not my argument. It is your argument and I don’t want to argue around it.”

Ooh. Let’s say that you’re again, presenting a road map and a team member or perhaps someone from another team asks you, “Are you suggesting that we should throw away four months of work in order to proceed on a different option?” That is what we call a loaded question. So, you are being asked a question that has an element of guilt built into it. It is a bit of a difficult situation to be in. It really relies on trust and what’s your relationship with this person. Sometimes there are no bad intentions, but a little bit questions usually do have. They feel like trick questions. So, kind of deflecting them is again about pouring it out that, “That is not my argument and it is not part of what I am supposed to answer” or what you will see kind of speakers do. They usually play ack questions completely differently and then answer them. So, this one is a loaded question.

Oh, another favourite; Atlas carrying the weight of the world. So, another aspect or opposite of a loaded question is you come in, present your own product and then tell your team, “Prove me I’m wrong and I might then reconsider something.” So, burden of proof is on the person propositioning and not the other way around because if you put it that way, it can be almost impossible to get someone to change your mind because you will not rationalise rationally. It will be extremely emotional to you. So, always remember that the burden of proof is on the person proposing something. Proposing a new feature. Proposing a new road map or whatever. They need to prove that that is a good decision and not the other way around. It is not others that need to prove to them.

A nasty one. If let’s say I’m proposing a product road map and then you might come back and say, “Yes Bruno, but I saw you make, for example heated up a fish dish in the company microwave and it really smelled bad and therefore I don’t think you are a really nice team player and so I don’t want to support your idea. So, instead of attacking my argument, you’re attacking me as a person and that’s not really valid and that is something that is called ad hominem. You will see that a lot, especially with the politicians; either answering criticism with criticism or attacking the person instead.

Moving to a connected one. I already hinted a little bit on it. Let’s say here, father and son and ideally, they’re working together and father proposes to the son, “Son, you know you should use this opportunity to work a little bit on your homework.” Son replies back, “Yes father, but weren’t you telling me that when you were young you were skipping school and you were not writing homework yourself.” This is something called appeal to hypocrisy. It’s basically answering criticism with more criticism. It’s usually a defensive move. So, kind of if you see it in your team again, do not assume that there is ill intent, but that there is actually a defensive mode. It is more common in large organisations, especially when there is contention for resources. So, kind of if the departments are clashing or even if it is two sections within the same department are clashing for resources, then one of the common tactics and logical fallacies is responding to criticism with more criticism. So, kind of trying to get the person propositioning to spend time and energy on defending instead of presenting more evidence, more arguments of their proposal is worthwhile.

The gambler. This time we will succeed. Though the gambler’s fallacy is in honour of gamblers themselves, especially when playing slot machines and it’s kind of like, “Okay now the third time is the charm. Seventh time is the charm. Thirty-first time is the charm. Seventy-seventh time is the charm. Let’s do it again.” In most cases, these are independent events. Basic probabilities don’t magically spill over to the next event. Independent is that the random chance is always random for that one.

Moving to the product and product development spectrum it’s not always that these probabilities are independent, but they most likely are. So, if you fail with something five times in a row; unless you can prove that there has been some significant learning and then the sixth time it is going to be somehow significantly different than the previous five times. You cannot connect them. You can call it gamblers’ fallacy.

Ambiguity. This is the favourite of politicians. It is basically what’s also known as double speak. You are speaking in such a way that it can be interpreted both ways and then if the interpreters’ interpretation doesn’t suit you, you can say, “That’s not what I meant.” Again, how I observe it in the larger organisations and product teams is mostly in a sort of defensive mode, especially if there is an aggressive manager or if there is an aggressive deadline, then you are presenting or arguing in such a way that you leave yourself a way out. That is something that if you see I wouldn’t suggest you aggressively call it out, but actually seeing okay, “What is the situation here? Is the problem in company culture? Is the problem that there is not enough trust and reliability between the people? Why is it happening in such a way?” Maybe that person needs some training and coaching to be more clear and kind of propose options instead of speaking in such a way that it is not clear or supported. You might also see that in very highly self-aware leaders that they try to speak in such a way because they are trying not to bias anyone else. So, kind of this one again, don’t assume ill intent, but try to find out what is happening.

Ooh, this one is something called special leading. It is basically when a person runs out of all the arguments or all the rational arguments that they can think of and then they plead for special cause and a good example is a psychic who claims that people need to trust his ability to read their mind in order for that to work because he has been disproven or debunked. A similar cause or similar situation within a product team might be when someone has presented some features and that persona has been debunked. Okay, we actually have everything. Customers don’t want it. This shouldn’t be built. The panic of that will be increased by that and that without any significant gain and then the personal resources people say, “Put some blind trust in them. Come on. Just hop on with me. Just put some blind trust.” That’s called special leading. Again, sometimes if the person is calling that out there is no need to be overly aggressive, but try to understand, “Okay how can I help that person bring out more evidence or search for evidence in a more structured way so that person can have a better argument instead of just believe me. Just take a leap of faith and jump through the window. Maybe that person is onto something”, but if you want to be more successful as a team, then help the person argue better.

This is similar, but instead of pleading for special costs you’re pleading to authority or appeal to authority. So, in large organisations the elevator talks, not elevator pitches, but you know those thirty-second elevator talks when someone comes, “You know, my boss’ boss said and therefore we should do that.” That’s what I heard. That’s what I heard in the elevator and so I think we should do that. Or the CEO said and we should… So that person doesn’t try to argue, for example the benefits, again the customer wants this. It will be impacted on the bottom line or something, but it appeals to some sort of higher authority. It doesn’t have to be within the organisation. This high authority can be on the outside. Maybe there is something new in the Church of Lean or in the Church of Agile or kind of referencing some thought leader and it’s kind of, “That’s how we should do it because that’s what’s been said.” That’s appeal to authority and on that one, just call it out. Just call it out and that’s it. Be aware of office politics and all that fun stuff which I hope you don’t experience that much.

Now, I have walked you very quickly through nine fallacies and the tenth one is kind of a warning when you become more aware of all of this that just because someone made a fallacy it doesn’t automatically invalidate what they were proposing. It’s a fallacy fallacy. So, kind of again, just because someone made a mistake in their reasoning it doesn’t necessarily invalidate their whole proposal. So, someone may still propose a good feature, a good update, a good product program, a good product strategy, but argued for it very poorly and that’s why I said in my recommendations previously, it’s kind of trying to be aware of what’s happening there. Try to help out first to make better reasoning, to find better evidence, to make better connections and see why did that come to be? What was explained wrong? People are not naturally well versed in rational presentations. It is something that we are attempting to build in school. In high school, in university education and what not, but still, it’s not that present. Laying out things very logically, very connected is not a common skill set. It is something that can be developed even without studying rhetoric at a PhD level or studying mathematical logic at PhD level, but it still requires some investment of time, energy and effort.

These are ten out of a massive list of hundreds of logical fallacies, but are some that are encountered most commonly within the product management space. This is the list because later, you will get this recording and everything so that you can go back and connect it. Now, after logical fallacies let’s look into cognitive biases. Now, these ones are ore difficult.  It is basically rooted in how our brains work with heuristics and to those of you that are coming from mathematics or software development, it is probably a familiar word. Extremely over simplified, heuristics is not algorithmic approach. It is basically based on experience and it’s a sort of a short cut. So, kind of you can quickly find the solution based on your experience in all the different brain connections that you have made over time.

Now, cognitive bias is a phenomenon where you consistently because of these connections in your brain, see the world as it actually isn’t. So, that is the simplest description of a cognitive bias. Again, it is seeing the world as it isn’t and here, I will share again, ten most common from the product management perspective and which better to start than the group think.

So, you have probably heard of the group think, especially with popularisation of methods like lean start up and customer development saying focus groups are bad. “It’s a group thing. Don’t do them. Avoid them” and what not. Yes, that’s true. What happens in the group think is basically exactly what it says in its name. There is a group of people and it is usually a few that start with taking the lead and then they start spreading those ideas and there are some phenomenon’s that I will mention a bit later that are all connected to group think and are amplified with it and kind of that starts shaping the decisions and the paths that others take. So, kind of being aware of group think is quite important. Now, what often happens is that other state. So, being aware of group think is quite important.

Now, what often happens and this is probably the most popular cognitive bias which is something called confirmation bias. Let’s say that what you know and how you see the world is the blue circle to the or at least my right. I hope it is your right as well.  Then that is everything you know and then the right circle is what someone is propositioning to you. So, you are listening to the presentation of a new product roadmap and it’s deadlines and it’s goals and what is supposed to be developed today and tomorrow and next month and what not, but what you are taking in is not everything, but what already complies with how you had your own preconceived notion of how that roadmap should look like and what should happen. That is the overlap between the two circles and that is confirmation bias. Basically, your brain subconsciously is filtering. So, this doesn’t happen at a conscious level. It’s not like you consciously say, “I am going to throw that into the garbage” or, “This is interesting.” It happens subconsciously that your brain filters and prioritises and supports what’s already aligning with the existing knowledge and preconceived notions of what should happen. That is confirmation bias.

Another one that happens in the group is anchoring bias. So, basically the first thing that we hear anchors us. Hence anchoring bias and we start subconsciously comparing everything to the first option. So, the first time is subconsciously and then we consciously start building the options around it. It’s a very popular approach with salesmen. So, kind of start with something absurd and then start with something realistic and that looks even more attractive because you started with something absurd. That also happens when you start discussing different options for developing either different scenarios or different road maps or different feature sets and what not. So, what we can be aware of is if you have different options, you can try to randomise them. That doesn’t matter in which way you discuss them. So, you try not to score them in advance, you try not to present them in any specific way. You just randomise them. If that is not possible then just put it out and say, “Okay let’s be aware of anchoring bias so that we are not comparing all other options to the first one, but that we are comparing to some…” They don’t need to be objective sets of metrics, but that they are agreed upon in advance. That’s why often, for example when designing new experiments, you want to predefine success or fail conditions so that you can compare to that instead of anchoring to the results that you get.

Another one that comes from the group environment and these poor guys; they are a stock photo, but I don’t think they dreamed they would ever be used in this way, but they will forgive us. So, another phenomenon that happens in the group think is something called the Dunning Kruger effect. Basically, the more you know, the less… not here necessarily. Maybe you are the most confident person in the world, but this effect is that the more people know, the less likely they are to speak up and ore likely they are to be less confident whole the other works as well; that the people who have the most superficial knowledge are most likely to speak up. So, here this gentleman in the middle; he might be sulking a little bit. “Maybe he’s right. Maybe I am over complicating it.” This guy is like, “Hey guys, what’s the problem? Why are we complicating this? Just do A, B, C and see what works and just move it on.” That is why it is often said that a group think is so dangerous because all these different biases happen in such a small pace of time. Basically, you can get the most vocal person who might or might not be the most knowledgeable person and kind of start anchoring and leading the discussion. Sometimes you want to say, “This is the decision we’re going to make. Let’s takeus from A to B”, but usually you want to have an open discussion and you want to have different options, you want to evaluate them openly and not bias because then you don’t end up with the best decision. You end up with the decision of a single person that was most vocal and had the ability to anchor everyone else and guide them to what they think is best. That is not always the optimal decision.

Now, this is not the same as group think. This is something that we call in-group bias. So, basically and this happens a lot within large organisations, but it happens with smaller groups of friends or start-up’s and what not. It is when you start preferring the opinions and arguments of those that you are closer with just on the basis of being close to them and not on the basis of them actually having good and sound arguments or something similar. If you want to fight this one it is first being aware of what the influence is. Does your relationship with other people influence directly how you think about their proposals? Do you support them just because they’re from your team or just because they’re your friend or on the merits of their proposal? We’re still human beings. It is impossible to completely ignore these relationships, but when it comes to actually making business decisions, decisions on where to spend money, what to develop, what to take to the market, it usually pays off to kind of minimise that a little bit. If there are people playing to that, playing games with you and others; trying to use that as some sort of a currency to get your support and approval to develop something instead of actually producing evidence, sound thinking, sound proposals, then it’s a good time to stop an kind of re-think, “Okay, what is actually happening here? Why is that happening and ho should I proceed?”

This one is painful, though what often happens is that when we are under performing or feeling a little bit under the weather, something is not going right, it’s a bad day and it’s not as productive as we wanted it to be. We can very, very quickly point to the reason why it is so. I had a bad sleep. I didn’t eat well. I’m under a bit of stress. I had a fight at home; something. There is always some situation and so we can argue very quickly that we will go back to our old performance level. We will be as great as we were before. This is happening not because of our character or character flaws, but because there was a specific situation. While when we see others under performing or proposing something we disagree on, coming up with an unrealistic product roadmap, we are quick to judge them on their character. “They’re a bad person. They’re not well educated. They’re clueless about this field.” That is something that we usually call fundamental attribution error. It is kind of, we judge ourselves based on the situation while we judge others and immediately say, “It’s a character flaw. That person is deeply flawed.” That bias is usually leading into ad hominem attacks, appeal to hypocrisy and it makes you go, “Okay that person first; it is their fault that they are like that.” Let us just keep hammering on that. This is something to be aware of and be more generous. Be more kind to others and kind of remind yourself, “Okay, I don’t know what that person is doing. I don’t know what that person is going through so let’s not immediately connect what’s happening right now to the character of that person, but rather there might be some situation that is happening.” That is very important for any leaders that are evaluating the performance of the employees and deciding either doing 360’s or deciding on the bonuses, on development plans and what not. Always remind yourself just like you are quick to find the situations why something didn’t go as it should have gone, so it is with others. It is not always a character flaw.

This one, this one, this one. Curse of knowledge. It happens to everybody, especially to us that are in the knowledge industry, a lot. Basically, human knowledge grows geometrically. It doesn’t grow linearly. So, the more you know, the faster you will beable to learn and the faster you will be able to come and suck in new things and the more you know, the less obvious things to others become extremely obvious to you and if you are not reminded of that, that is a recipe for disaster and frustration for both yourself and everybody who is working with you. That’s why it is always important to kind of go back and double check with people. That’s why I say, explain like you are ten years old. It is not about mocking someone, but it is a reminder that, Hey, just because something is obvious to you, based on all the knowledge and experience you have, it doesn’t mean it is obvious to everybody. It doesn’t mean that others are idiots or stupid or whatever. It just means that they still haven’t made those connections so then be respectful and explain. There is always something that you don’t know as well.  Curse of knowledge can be quite damning. I felt it myself a lot of times, especially when working on different management systems and what not because you are explaining to someone, for example portfolio management. We need to have a set of product families so we can compete easier. The people are all okay. I mean yes, I mean principle, but they don’t see the connection or they don’t see why will a portfolio approach be better than unaligned approach. Why would a set of strategies be better than a single strategy and what not? So, you need to bring them out and keep explaining again and again and again and again. Never assume that people know everything. I even found to some extent that sometimes it is better to be accused of being a little bit patronising than to have everybody nodding their head vehemently agreeing and being extreme, “Yes, yes, yes” and then finding out that people agreed on completely different things because everybody understood everything differently.

I’m cheating on this one a bit. It is actually one picture with two biases. So, we have two sides of the same coin. You can be overly optimistic or you can be overly pessimistic. Both of these are biases that are unhelpful. So, kind of this optimistic bias is something that is plentiful with entrepreneurs, start up founders and what not and usually manifests as wishful thinking. “It will be within 5 years we will be swimming in money. Within 5 years, market penetration is going to be 30%.” Good luck. It’s what is very dangerous when we are planning MVP’s, product road maps, go to market strategies; the list doesn’t end. The best antidote of course is testing and kind of reducing this wishful thinking to something more probable. Now, pessimism or pessimist bias you would think, “Okay, well what is bad with that?” It is always better to be safe, a bit secure. Not really. This is going to the extreme. This is always thinking the world will end, always thinking the products will never succeed. Just don’t launch it andjust hunker down. Hunker down, keep doing what we are doing and just hope that everything passes through. Again, while this is the opposite of optimism bias, it is still extremely dangerous to the team because you won’t be able to plan efficiently or propose again efficiently and I kept my favourite for last.

I wish I had you here in person so I can ask you, “What is this?” This one is I am confident that everybody on this call, everybody who will ever watch this video did at least once and it might even be at least once consciously.  It is the favourite; the sunk cost fallacy. Basically, we spent so much that we should just keep doing it. I mean we spent so much on this ship. Let’s just repaint it and give it one more go. I had a really ridiculous happening once and I was really angry at myself because I felt prey to this bias even though it has fallacy in the name.

So, I live most of the time in Oslo; in Norway. Here it is a snowy country. It has a lot of snow and a lot of ice and what not and so one day I was waiting for a bus and it was just snowing and on the bus stop I have a bus going every 15 minutes and it was late. It was a bit delayed. The snow was falling. I am already waiting for ten minutes. I said, “I have been waiting for ten minutes. I will wait a little bit longer.” So, I waited for ten minutes more. Now, I am already very late to my client meeting and it is already 20 minutes. So, I am looking and I have been waiting for 20 minutes. I could have gone to the metro stop by now at least twice, but I have been waiting for so long that I will wait for this bus. I wait for it another 20 minutes. Now I am aware already and I am thinking to myself, “This is just pure sound cost. Common.” I should just throw away those minutes and just walk to the metro stop, but my brain doesn’t let me. My pride doesn’t let me. No, I will wait for this bus now and go into the bus and I will take that bus; two stops to go on the metro. So, 17 minutes after that; so, what was that? A total of 57 minutes of waiting. I got on my bus that was packed. So, I barely went in and I went two stops to hop on the metro.

This fallacy is very, very real and that is something I always suggest to just call it out. You spent something and it is no argument to keep doing something. Those cases are quite unique. If you are a start-up, if you are even a product team, it is highly unlikely that all the costs spent up until now should qualify as a valid argument for keeping on doing the same thing.

So again, an overview of these ten biases and what brings them together. So, kind of the first line, I put mostly what's around group think and related to that. Group think is most destructive because it amplifies all the other biases because when you get the person that’s also suffering from Dunning Kruger amplified knowledge of whatever topic you are discussing end being over-confident and then the person starting is either anchoring everyone in terms of issues or solutions and it’s mostly in terms of solutions and that’s when you get into trouble because you’re jumping to solutions that have been unproven and have no good thinking behind them, but it is the integration.

So, kind of around group biases confirmation bias is always present. It just is always present. It is our subconscious filtering and what I want to go to for the roughly next ten minutes and then I will check for questions. So, a reminder that at the bottom you have a Q&A box. So, better decisions I find them to be both individual and a themed sport. It is possible to fight all these fallacies and biases and it’s not even that difficult, I promise.

So, kind of four areas where I usually coach and work with teams and what not, that I speak about. So, just by going through this together with me and staying curious and going back and re-watching this, making your own notes and basically building your own awareness around these logical fallacies and cognitive biases is a massive, massive, massive step. As I say, this isn’t rocket science. You don’t need to understand why that happens. You don’t need to have this at the PhD level, but just being aware if someone is doing ad hominem or is responding to criticism with criticism is massively helpful. Being aware of it in a group, there is an anchor now. There is a massive anchor. Are we discussing the right issue? Why are comparing all the options to the first option? Just being aware of that, being able to call it out and discuss it is a massive step; massive improvement.

Now, connected to that is visualising and psychological safety because if you don’t have the psychological safety within the team or a group of people that you are doing this with, it will be very difficult to openly call out things. It may be perceived as an attack. Basically, why are you calling my thinking bad? I don’t understand. Why are you attacking what I am putting forward? We are still emotional and we are still prideful and passionate people, especially those working in product development, R&D and what not. I remember when I was designing my stuff, it is like someone is attacking and chipping at my soul. It’s like, “Yes, they are not criticising me, but they are criticising something I made with my intellect and my time” and so having the psychological safety is very important and what I found works very well is visuals; both visuals as I have shown you; kind of putting a visual for every fallacy and bias, but also actually visualising what you are discussing. So, kind of if I just have a piece of paper, but if this is a road map, we are discussing that. We are discussing these features.  We are not discussing me or you, but together, we are discussing what’s wrong. What’s illogical with this? What’s illogical with that argument? What’s illogical with the proposal? So, you are together. You are and I are attacking in this assembly and criticising this to get better. So, kind of, you visualise the object of contention. You visualise the object of discussion and finally, the fourth one is proactive discipline.

So, this is something that doesn’t come naturally. It doesn’t feel natural as well. That’s perfectly fine. I mean if you are going around and just like, “Oh, a bad argument. Seven fallacies in thirty seconds.” It’s not helpful at all. So, it’s important to keep this discipline to build habits slowly over time and kind of to pick those moments. So, especially when I am actively looking for elements like this is when we are talking about experiment design, interpreting results, for making big decisions and big decisions are relative. So, kind of a big decision is anything that requires a substantial amount of time or a substantial amount of resources and I specifically separate time from resources because time; if you take a resource of time, it is very dangerous because you can never buy back more of your own time. You can perhaps try to buy someone else’s time, but that’s not your own time. So, kind of looking at does it require a substantial amount of time. Money or something else? Then it’s a good time to invest in, “Okay, we should think. Are we thinking bad? Would this be a bad decision? Are there any flaws in the thinking? Are there any biases that are present there? Is there something invisible?”

Again, psychological safety here is important. This is tremendously helpful if you have someone else to discuss it with; be it a team or someone outside of the team or what not. That’s what they usually have keep the beginners mind because they say the beginners mind sees what others don’t. An expert mind sees only one solution. So, that is sometimes why it is helpful to step outside of the team and ask, “Okay, can you review? Does this make any sense at all to you; kind of what we are proposing here? The MVP; does it make sense to you? The features that we decided to go with first; the go-to market plan that we decided on, the product road map? Who knows? Maybe they will see something that you haven’t seen so far.

So, these four cost nothing to implement. Okay maybe they cost some friends if you are too aggressive, but it is part of the learning. It happens. As I say, you can start tomorrow with that; becoming more aware either going back to this presentation and writing down what I said or printing it out or making your own visuals for every fallacy and bias and then just pulling them out when you are working on some paper or something.; “Okay my thinking is bad” or, “Okay this is how I can improve it” or where you are working together with a friend and kind of calling it out.

Now I will check quickly the Q&A box if I can? Well, I see something. I see a lot. Okay, I’m trying to move this Q&A box.

Q: Could you recommend some resources to help your team argue better and lay out arguments more logically?

A: I hope that I’ve given some good proposals and now as I said, the easiest way to start with a team is actually visualising what is the object of discussion and then slowly over time build this capability. Awareness is the first step and as I said, this is not something that naturally comes up. So, yes, there are some resources. I cannot share them in this format, but I am happy to share them actually in the next slide. So, because of the limitations of the format, what I decided is that you can just fire me an e-mail and I will share any resources that might come handy to you. What I like using myself, personally is a deck of cards from School of Thought. I don’t know if they still print them. I backed their Kickstarter campaign. They are basically gamifying calling out fallacies and biases. So, kind of if I remember right, it is deck with 48 cards and we can design games with it. I designed a specific workshop with it, but basically you can shuffle. You can have some drinks and kind of go out and people can pretend what kind of fallacy they’re doing and everybody else must guess it. So, that is a fun way to introduce it. What I definitely suggest to not do; if you go and search online for cognitive bias you will find that big graphic with a brain in the middle and I think 108 biases around. That’s great for kind of referencing and looking at it, but it’s total cognitive murder, overkill to the point of being almost useless because cognitive bias as a psychological field is still pretty undefined and contested for and the more granular you get, it’s actually less and less useful so then you then have 20 to 30 top biases and they are pretty similar then it is fine.

The ones I selected for today; ten are fallacies and ten are biases are the ones that let’s say are the most common and most destructive within the product management environment and so that is what I suggest starting with and then finding specifically something that everybody in the team  agrees with and discuss that. Now, in proving arguments has a lot to do with improving writing as well. Oral rhetoric is something that most feel confident or comfortable with, but it’s actually improving the writing; thinking through writing and refining arguments that is the best. Who was it; was it Ben Horowitz? Perhaps it was Ben Horowitz. I don’t remember, but basically who said, “I don’t need a product manager who cannot write. That’s it.” It’s kind of for hiring what he was doing demanding that potential product manager would write a specification or proposal or something else. So, what I found best is this writing, writing, writing and if someone cannot argue for something on a page, there is a lot of work to be done. So, just reach out. I am happy to share more resources on that. Let me find a way to find the Q&A box.

Q: Okay, how to personally deal with Dunning Kruger effect? How to personally deal, but not collectively.

A: Let’s take a look at both spectrum's. So, Dunning Kruger says that if you are very, very knowledgeable you are probably less confident and if you are superficially knowledgeable in something, it is that you are over-confident. So, the best way or at least how I try to deal with it myself is kind of trying to remain humble. So, let’s look at why are these people that are more knowledgeable, why do they feel less confident? Well, the theory goes that they feel so because they are more aware of the things that they still don’t know and the things they still have to learn in order to get even better and they are also aware of the path that they have taken. The opposite is those that are kind of superficial. Because their knowledge level is so low, they cannot actually appreciate the problems and the road blocks waiting ahead. So, let’s say that we are all in somewhere on that spectrum. Like in specific areas you are very knowledgeable and in most others, you are very superficial and so the first and the best is remaining humble ad kind of reminding yourself, “Okay I always have something more to learn and there might be something that I don’t see that others see for a multitude of reasons.” That’s number one.

Number two, in what you are knowledgeable; I almost swear it. I will refrain myself. In what you are knowledgeable recognise and acknowledge that, write it down in whatever way it helps you and start. Some people, it helps them to step into the front of the mirror and say, “I know this and that. I know this, this and that.” Practice your confidence. Practice sharing that knowledge. What’s good, if you are more introverted than extroverted, is teaching somewhere. Remotely now obviously respect all the instructions of your country. Teaching and coaching others in something you are very good at because that is… if you can teach, that is the ultimate proof that you are actually knowledgeable. That should help you build that confidence. You’re not being cocky. You’re not being a loud mouth. You are not being arrogant. If you are able to stand up and speak up “This is what I know, based on my experience and therefore that has weight.” That is perfectly fine.

Now, going to the other spectrum, it is about being infinitely curious and it is to some extent having a beginners’ mind. So, if you are aware that, “Okay, I actually don’t know a lot about this field so perhaps those people that are speaking up and are sharing something; there might be so merit in it. So, I want to listen to it. I want to get the soundness of it. I want to measure it on that before I speak up or before I share more.” What might happen or what happens often to me is when I get called in, I don’t know all the industries. What I know, for example is how to think well. What I know is how to think bad. What I know is some specific system. As I said, I used to work as an engineer and used to work on pretty massive systems so I can recognise that. So, I am relying and looking to the world through that lens and even though I am less experienced in some fields, that’s what I used to judge the situation and then when I speak out, I will be careful with my words.

I will not speak out saying, “You are wrong” or, “This is not correct”, but rather rephrase the question. That would be a loaded question. As I said before is kind of, “Okay, this is what I heard and this is what I understood. Therefore, I am making this conclusion. Does that make sense to you?” So, that way I remain humble. I remain curious. I am taking something that’s illogical to me and I am trying to find out why is that illogical to me? Maybe it is just me. Maybe they didn’t present their argument well enough. Maybe it’s something else. That is how I at least try to not to get rid of – you can never get rid of any of these biases. It is our brain. You can rewire it a bit differently, but how I try to minimise the effect of Dunning Kruger bias.

I hope that’s helpful? Just reach out again if you would like to continue this conversation.

Let me check. I will take one more and then we will slowly wrap up. Oh, the joys of… okay. Thank you, Alexander. Any book authors; can you specify books on what and while you are specifying, I will start talking anyway assuming the questions’ intent. So, interestingly this field… so I like using this word. Why do we invent the work? If you want to be efficient, effective, fast, smart and what not; re-use other people’s work, of course with all the copyright respect and everything.

So, it is kind of what you will find this is about is usually if you try to search online, mental models. That is becoming a really, really popular topic even though biases and fallacies don’t fall into mental models although some of them will be there. Research into cognitive biases is mostly filled with applied psychology and behavioural psychology and I mean, it is academic papers. It is a boring read. Yes, it might be worthwhile if you are doing a PhD, if you are starting to investigate deeply into it. The most accessible materials that I found is from School of Thought. I think that they basically aim at K-12 in the USA; the type of education, but they really try to make it in plain English. It is not a book. As I said, it is an online web page. It is interactive and you can click on different biases and fallacies and find out a little bit more about them. They are not extremely in depth, but as I said what I found works at this level is building awareness. You don’t need to be a doctor of science or a doctor of philosophy in this specific subject.

Another book that is helpful is Tiny Habits form B.J. Fogg. That’s actually not on fallacies and biases, but it is about exactly the title of the book; building those small habits because that is helpful in changing this. So, you can start following the recipes from the books. The main premise of that book is you find that existing habit or existing way of doing something and you latch onto it. So, for example this is an extremely trivialised example. When my feet hit the ground when I get out of the bed, I will drop on the floor and do three push up’s and then when I go up, I will give a high five to myself. That’s a very trivial example of the formula, but you can use that formula to actually build up awareness around different fallacies and biases. For example, before I speak up, I will consider if other people have had a bad day. I just imagined this one, but that would, for example help you reads fundamental attribution bias.

For more, just hit me up on this e-mail and I am happy to share all the resources that I have. We will wrap up now. Any question that was unanswered, again, just drop it on this e-mail and I am happy to help out.

Before we close, I would just like to remind you to – I forgot the link – forgive me, but keep growing, stay home. Keep growing. There’s a website with all the events coming up. Please check it out. There’s a lot of exciting events coming up from growth hacking, innovation, personal wellbeing which is very important in this time with all the anxiety and stress on the world. So, please look it up. Everything is free to sign up. Invest in yourself. Now is a great time to invest in all the topics because when this ends and this will end, you will really want to hit the ground running and kind of be ahead of the pack and just enjoy.

Okay, that’s it. Thank you very much and see you at the end of the month.


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Avoid stupid decisions: most common cognitive biases and logical fallacies (webinar recording) by Bruno Pešec is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.
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Webinar transcript

Avoid stupid decisions: most common cognitive biases and logical fallacies (webinar transcript) by Bruno Pešec is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at

Bruno Pešec helps business leaders dramatically increase returns on their investments in innovation.
WebinarLogical FallacyCognitive Bias

Bruno Pešec

I help business leaders innovate profitably at scale.


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