I recently read The Design of Everyday Things, a brilliant book about design and psychology. It dealt with a lot of topics that are crucial to good design but aren't obvious. The author, Donald Norman, is a psychologist and approaches design from that point of view. His view, which I agree with, is that use trumps aesthetics. They aren't mutually exclusive, of course, but if you have to choose one, ease of use should always win.

The book deals a lot with how human memory works, how mental models of objects or processes are created, the different types of errors that can be made and what design can do to minimise them. Two things really struck me.

First, knowledge is stored in two places. It can be in the world, like a pocket map of a foreign city or a user's manual, or it can be in the head, like your knowledge of the alphabet (one would hope it's well ingrained by now). Each has its advantages and disadvantages. A prime example are log tables. No one uses them anymore but it was once considered an important skill (or at least useful) to have the important ones memorised. The calculator has rendered them completely obsolete. The knowledge that was once required to be in the head (memorisation) is now found in the world (the calculator).

This idea of one type of knowledge displacing another intrigued me. The internet, I imagine, will do to a lot of media what the calculator did to log tables. It moves a lot of knowledge that used to be in the head into the world where it is readily accesible. It can even render useless other forms of knowledge in the world. Encyclopedias are already thoroughly obsolete. I grant that a lot of the internet is unreliable but over time this will improve. As a source of knowledge, there is little that can match the power of the internet.

The second idea that caught my attention was a section on how people form and store mental models. As an example, if you enter a house you've never been to and you wanted some water, where would you go and what would you look for? Perhaps the kitchen or the bathroom, there you might a faucet, right? Even though you don't know for sure there is one, you expect there to be one because you have a mental model of a house and that includes a faucet in the kitchen or one in the bathroom. What if you went to a house that had a pump instead of a faucet? I've been to more than few cottages where this was the case. Would you then expect to find pumps in all the other houses you would visit from then on in? I doubt it. Likely, you would remember the exception but still hold the main model as the true one.

The book, however, says something very interesting about this. According to the text, the mind does not weight these instances as mathematical relations. If you go to 100 houses and 2 have pumps, what your mind does is form two models, the generally true one (faucet) and the exception (pump). The mind will give them equal weight in your memory and you will recall one as easily as the other. In fact, the mind seeks out exceptions and even relishes in them.

We remember them, talk about them, and bias behaviour towards them in wholly inappropriate ways.

To me this explains a lot about journalism, and not just today but through history. The news is almost exclusively about the exception. Not the fifty healthy babies born today but the one siamese twin with a shared heart. Not the ten days of peace but the one day of violence. Not the thousands of pedestrians who make it across the road but the one person who got hit by a car.

It also speaks to me about human fear. If my mind holds the innumerable safe flights that happen around the world daily in the same regard as the tiny chance that something disastrous might happen, then I could understandably be afraid of flying. If, in my mind, it is equally likely that a spider might bite me as not, despite having seen hundreds of spiders and not having been bit once but hearing about the exception and giving it equal weight to the norm, then an irrational fear suddenly becomes quite rational.

It's a fascinating book about a topic I knew very little about (a theme in my reading these days) and I highly recommend it.