First principle thinking & Five Whys

Following link will take you to an ad by German Train. You don’t need to speak German to understand the ad! This ad gives an accurate summary of the discussion that follows!

It is said that asking “why”, is a sign of curiosity. If you have spent your life or even a few hours with a toddler, you would know ‘why’ I am saying so! You might reminiscence the early you as well asking those questions. In some cases, it could be the same question over, and over again! 

I recently came across an article explaining the theory of Five Whys. It is so interesting and relatable, that I said to myself – why not share it with others! The technique pushes you to drill down and ask yourself why something happened and do it five times – A question for the answer to the previous question.  On the fifth iteration, you would usually reach the root cause. 

Toddlers know little on how to abstract (No! – don’t get any more ideas from the above clip. Let us limit our discussion to toddlers. And please don’t ask me why!). The ability to abstract is developed later in life and is essential for survival and progress. (An ability that is becoming under question by our late-night cravings to explore Wikipedia though!)

Abstraction is part of our fight or flight reaction. When a gazelle looks at a lion running towards him, he doesn’t stop and think – why? By analogy he knows what this situation can lead to. So, he runs and rightly so. Analogical thinking also helps mankind make progress. You don’t have to first develop a proof of underlying physics of electronics components to create new devices. We don’t first develop an understanding of how a compiler was built to develop a program. We abstract ourselves from these things and concentrate on our task at hand instead. 

Reasoning by analogy helps us draw quick conclusions about new events based on the previous knowledge of similar happenings. While analogical thinking is good in many ways, it becomes a hurdle for problem solving or doing innovations.  Imagine your internet connection at work goes through a blackout every day in the morning for half an hour. Chances are that we just draw an analogy that such things can happen for short durations of time. So, no one asks why. May be there is an incorrect network policy in place. May be a component is set to reboot everyday at the given time in the network. We will never find out about it unless someone asks why we get these blackouts. 

One of the reasons why people don’t ask “why” is that they don’t want to sound annoying. Your habit of persistent enquiry can buy you a questionable reputation! People may regard it as a trust deficit – “you never believe what I say” and a nagging boss kind of situation. Someone who does not know things technically – and only pushes his weight around by asking ‘why’ questions. (S/he only gets paid for asking “why”. Why doesn’t S/he solve the problem for a change!)

I’ve seen many situations in which people responsible for a domain fall short in their troubleshooting efforts by stopping at the first cause of the problem. They seem to like Billy Joel’s song – “Don’t ask me Why”. They do not give enough thought to go deeper in their troubleshooting effort. Doing so may sound simple and logical while reading this text. However, trust me, practical experiences are much different from this.  

Originally developed by Sakichi Toyoda in 19th century, the Five Why technique found widespread application in Toyota Motor Cooperation thanks to Taiichi Ohno. It became a key component of the problem-solving training imparted at Toyota [1]. Asking the question five times, promotes deep thinking and helps drill down to the true cause of the problem at hand. 

The technique was initially used for new product development. It represents first principle thinking (in contrast to reasoning by analogy). It breaks down the idea to its basic proposition that can not be deduced from any other proposition [2]. It is said that without this, innovation would be impossible.  For example,  A very common example cited these days is how Elon Musk brought the concept of electric cars to reality. Reasoning by analogy would lead us to believe that a car driven by batteries would be an inefficient and expensive car. This changes altogether when we reason by first principles. 

You can apply first principle reasoning to everyday life as well. Why can’t you lose weight? Reason by analogy. You may draw the conclusion that weight increases with age as metabolism slows down. Now try reasoning by first principle and see if you can find another reasoning!   

To end this discussion, here is another example of root cause analysis from poetry, and how a simple thing can have large impact. You can never find out unless you ask five whys. Interestingly, the poem was written in the seventeenth century!  

For want of a nail the shoe is lost;

For want of a shoe the horse is lost;

For want of a horse the rider is lost;

For want of a rider the battle is lost;

For want of a battle the kingdom is lost;

And all for the want of a horseshoe nail

–         George Herbert

[1]: Ohno, Taiichi – Toyota production system: beyond largescale production

[2]: https://en.wikipedia.org/wiki/First_principle