Decisions Part I - What's a decision anyway?

The word decision pops up very often in our day to day conversations, and that is not that surprising. Decisions form a very central role in our lives: we can easily sum up someones life by telling the sequence of decisions they made throughout it. We judge ourselves and other people by the decisions that we make:

  • I can’t believe they are moving in together, that is just a nightmare waiting to happen…
  • You should ask your brother to go with when buying your car, he bought a really good one himself.

The sad thing is that most of us never really learn anything about making decisions.

A Philosophy of Software Design by John Ousterhout

Since I mentioned this book during my interview with Dave Rael for the podcast Developer on fire, I thought it was time to put my favorite quotes of the book online.

A Philosophy of software design looks at the creation of software through the lens of complexity in your system. This book is very small, only 200 pages, so don’t expect an in depth explanation of every topic in it. It covers the basics of every topic and it is up to you to venture out and find a more in-depth book about one of the topics in it.

The most fundamental problem in computer science is problem decomposition: how to take a complex problem and divide it up into pieces that can be solved independently. (Location 198)

Decisions and their outcome

Decisions versus outcomes

Do not confuse the outcome of a decision with the decision itself. You can make a good decision but the outcome of it can still be bad… and visa versa

The decision, it is yours. The alternatives you have belong to you. You have total power over the alternative you select, but seldom over the consequences of selecting that alternative.

Abbas, Ali E.; Howard, Ronald A.. Foundations of Decision Analysis, Global Edition (Page 26).  . Kindle Edition. 

Or to put it very simple: a decision and the outcome of it are two separate things and therefor should be measured separately. One of the best examples we have to distinguish the decision itself from the outcome, is when we talk about drunk driving. Although many people come home in one piece after drunk driving, almost everyone will agree that it is a bad decision to take the wheel when drunk. We also understand that people get in car accidents when sober and that this does not mean it was a bad decision to drive.

Unfortunately for us, this is one of the few clear scenario’s where we understand the difference between the quality of a decision and the outcome of it. Most of the time it is more cluttered than that. Think about the following: is it a bad decision to mary someone when it ends in divorce?

We often confuse these two concepts. We talk about making a good decision when the outcome of it was good and visa versa. This is such an important concept, yet it was not until I started reading a book about poker that I came across a word that captures the meaning of our confusement between decisions and their outcomes:

our tendency to equate the quality of a decision with the quality of its outcome.

Duke, Annie. Thinking in Bets (p. 7). Penguin Publishing Group. Kindle Edition. 

So when we talk about a good decision, we should talk about the quality of that decision, not about the quality of the outcome.

There need to be a couple of basic elements present when you want to have a qualitatively good decision. I will talk about in my next blogpost.

The 6 main elements of a decision

  1. A decision maker

A decision maker is a person with the authority and the commitment to make a decision.

  1. A frame

  2. Options

Options are available actions that the decision maker can take that will lead them to a different future. If you have multiple options, but all lead to the same outcome, than you have no decision to make, because it does not matter which one you pick.

  1. Preferences

A decision maker will have preferences about the options. This means that certain options are more desirable, because the outcomes of those options are more desirable.

If the decision maker does not prefer one option over the other, they don’t care about the possible futures. This means that there is no decision to be made, because any option will do.

  1. Information

The linking of what the decision maker can do (options) with what they want to do (preference) is provided by what they know. What they know is called information.

  1. Logic

A process to derive the action we should take from what we can do (options), what we want to do (preferences), and what we know (information).