Spent – Sex, Evolution and Consumer Behaviour by Geoffrey Miller

I’ve been postponing to write about this book simply because I still am overwhelmed. Geoffrey Miller works in the field of evolutionary psychology which brings him extremely close to the currently very fashionable field of behavioural economics. And I am extremely intrigued to learn why we all actually behave the way we behave.

Particularly, I am spooked by the way I behave. On the one hand I have my ZEN inspired days. Less is more, breathe. The most important things in life are free. On the other hand, I have days where I crave things like powerful cars, the next watch, a slightly bigger living room. We all know how this works, I guess.

Miller’s book is all about behaviour, particularly about our spending behaviour. It put me at ease with myself. It explained to me why I behave the way I behave.

Geoffrey Miller manages to explain, why some people buy Hummers (without condemning them) and why others blog – all in the same book.

The book is extremely well written, funny, witty, well researched. There is no reason why you should not go and buy it now (use the link below, so I can afford more conspicious consumption). I was laughing loudly in my airplane seat when I read the story about Gérard, the Cro-Magnon and modern man from the future.

But just as an exercise, let me try and summarize from memory:

  1. Most of the objects we buy, are signals that we as hypersocial animals send about ourselves. Conspicious consumption, can be broken down into conspicious waste (Hummer SUV’s), conspicious precision (the Rolex watch) or conspicous reptuation (here comes facebook into play).
  2. There are only six defining (and mostly stable) personality traits everybody has: Intelligence (G), Openness (O), Conciencousness (C), Agreeableness (A), Stability (S) and Extraversion (E), combined and to memorize them better: GOCASE, like I can go along or wherever with that person…
  3. Evolutionary, it is very important to communicate your personality traits and relative fitness indicators to others, either the real ones or the ones you want others to believe you own. This happens not only when girls by mascara or boys go to Gyms but as least as importantly,
  4. We spend most of our time buying and displaying other fitness indicators as well. Intelligence (blogging for example, discussing books about behavioural economics), Openness (displaying our political views), Agreeableness (driving a Prius instead of a Hummer, or driving the BMW if we want to express that we are less agreeable), Concienciousness (by sticking to a hobby that requires meticulous attention to detail), Stability, or Extraversion (think about that pink hat that Girl wore at the party or facebook again). All this is mostly just signalling to others. If I buy a rifle, I could as well say: I am not dramatically open, and my agreeableness has it’s limits. Much easer to buy the rifle.
  5. Without being judgemental, Miller  then goes on and suggests that very often instead of buying all these things to say something about ourselves, we very often much rather could talk to people, which might work better (and would also dramatically improve our resource efficency in my view). His lists of things in life that really matter are a nice reminder.
  6. Getting even closer to behavioural economics, Miller gives a lot of support of a tax system that taxes consumption more than creation (work).

Only on the last pages, the nice and easy pace of the book accelerates a bit and the professor is released. Seems like he liked to squeeze just a couple of more thoughts in.

But that does not diminish the fact that when I started reading the book on Kindle*, and I tried to mark the best quotes and passages, my ‘notes’ section quickly got to more than 20% of the book. I am a big fan.

Buy at Amazon (DE):

* a purchase I made to show off my intelligence (reads), openness (to new technology) and whatever

Tags: ,


  1. Sample sent to my Kindle. Thanks for the suggestion 🙂

    ##idea start##

    book reading club that can send each other samples to their kindles 😉

    ##idea end##

  2. Hi Stephan,

    1. Nice redesign of your blog!
    2. Great summary, not too much, not too sparse – just the essence!
    3. Just wanted to help you getting your next watch / enlarging your living room by buying that book over your referral link, but it’s broken. Too bad, so sad 🙂

    Anh Tu

  3. Stumbled across this post through Ahn Tu’s tweet. Usually I’m not so much into psychology. But one thing really stroke me when reading this.

    To be honest. I can’t remember a single day I wasn’t craving for a faster car. But I guess I’m just a petrol head.

  4. There is no other motive for buying a Hummer – or a SUVish “muscle” car – than bare egoism combined with a good portion of stupidity. However, thanks for recommending this book. I will have a look at it!

  5. thnx. Sounds very interesting.

  6. @Anh Tu Sam: Thanks for the comments. Not sure what went wrong with the Amazon links.

    @Marc You will enjoy the section that Miller has devoted to SUV brand names 🙂

  7. bought it

  8. @Oliver Thylmann: ditto.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.