Why is it so hard to give good directions?

We’ve all been there – the directions sounded so clear when we were told them. Every step of the journey seemed obvious, we thought we had understood the directions perfectly. And yet here we are miles from anywhere, after dark, in a field arguing about whether we should have gone left or right at the last turn, whether we’re going to have to sleep here now, and exactly whose fault it is.

The truth is we shouldn’t be too hard on ourselves. Psychologically speaking giving good directions is a particularly difficult task.

The reason we find it hard to give good directions is because of the "curse of knowledge", a psychological quirk whereby, once we have learnt something, we find it hard to appreciate how the world looks to someone who doesn't know it yet. We don’t just want people to walk a mile in our shoes, we assume they already know the route. Once we know the way to a place we don't need directions, and descriptions like "its the left about halfway along" or "the one with the little red door" seem to make full and complete sense.

But if you've never been to a place before, you need more than a description of a place; you need an exact definition, or a precise formula for finding it. The curse of knowledge is the reason why, when I had to search for a friend's tent in a field, their advice of "it's the blue one" seemed perfectly sensible to them and was completely useless for me, as I stood there staring blankly at hundreds of blue tents.

This same quirk is why teaching is so difficult to do well. Once you are familiar with a topic it is very hard to understand what someone who isn't familiar with it needs to know. The curse of knowledge isn't a surprising flaw in our mental machinery – really it is just a side effect of our basic alienation from each other. We all have different thoughts and beliefs, and we have no special access to each other's minds. A lot of the time we can fake understanding by mentally simulating what we'd want in someone else's position. We have thoughts along the lines of "I'd like it if there was one bagel left in the morning" and therefore conclude "so I won't eat all the bagels before my wife gets up in the morning". This shortcut allows us to appear considerate, without doing any deep thought about what other people really know and want.

“OK, now what?”
This will only get you so far. Some occasions call for a proper understanding of other people's feelings and beliefs. Giving directions is one, but so is understanding myriad aspects of everyday conversation which involve feelings, jokes or suggestions. For illustration, consider the joke that some research has suggested may be the world's funniest(although what exactly that means is another story):

Two hunters are out in the woods when one of them collapses. He doesn't seem to be breathing and his eyes are glazed. The other guy whips out his phone and calls the emergency services. He gasps, "My friend is dead! What can I do?" The operator says "Calm down. I can help. First, let's make sure he's dead." There is a silence, then a shot is heard. Back on the phone, the guy says "OK, now what?"

The joke is funny because you can appreciate that the hunter had two possible interpretations of the operator's instructions, and chose the wrong one. To appreciate the interpretations you need to have a feel for what the operator and the hunter know and desire (and to be surprised when the hunter's desire to do anything to help isn't over-ruled by a desire keep his friend alive).

To do this mental simulation you recruit what psychologists call your“Theory of Mind”, the ability think about others' beliefs and desires. Our skill at Theory of Mind is one of the things that distinguish humans from all other species – only chimpanzees seem to have anything approaching a true understanding that others' might believe different things from themselves. Us humans, on the other hand, seem primed from early infancy to practice thinking about how other humans view the world.

The fact that the curse of knowledge exists tells us how hard a problem it is to think about other people's minds. Like many hard cognitive problems – such as seeing, for example – the human brain has evolved specialist mechanisms which are dedicate to solving it for us, so that we don't normally have to expend conscious effort. Most of the time we get the joke, just as most of the time we simply open our eyes and see the world.

The good news is that your Theory of Mind isn't completely automatic – you can use deliberate strategies to help you think about what other people know. A good one when writing is simply to force yourself to check every term to see if it is jargon – something you’ve learnt the meaning of but not all your readers will know. Another strategy is to tell people what they can ignore, as well as what they need to know. This works well with directions (and results in instructions like “keep going until you see the red door. There’s a pink door, but that’s not it”)

With a few tricks like this, and perhaps some general practice, we can turn the concept of trying to read other people’s minds – what some psychologists call “mind mindedness” – into a habit, and so improve our Theory of Mind abilities. (Something most of us remember struggling hard to do in adolescence.) Which is a good thing, since good theory of mind is what makes a considerate partner, friend or co-worker - and a good giver of directions.

courtesy of bbc.