As I said before, asking people "do you see things that aren't there?" (blogs passim) is part of the diagnosis process used by the medical profession when assessing people for mental illness. Apparently, seeing things that aren't there - i.e. seeing things that the doctor doesn't see - is an indicator that you are suffering from mental illness.

In 1975, a British architect by the name of Norman Foster was quite obviously suffering from some kind of mental illness, since he saw things that weren't there. Spanning a valley over the river Tarn in southern France, he saw the tallest bridge in the world - only 30m shorter than the Empire State Building. He saw a way of constructing this bridge that nobody else in the world could see - instead of hanging the road deck from huge columns, he'd build the road deck on one end of the valley, and slowly push the whole thing across to the other side.

The man was, if you follow the flowcharts used by the medical profession, quite obviouly clinically insane.

He is cured now though, and has been cured since 16 December 2004. On that day, the Millau Viaduct was officially opened. It's the tallest bridge in the world, only 30m shorter than the Empire State Building. It was built using a brand-new technique - pushing the road deck out across the valley inch by inch.

Since everybody else can now see what Norman Foster sees, that means it is real and he is no longer suffering from any kind of delusions.

Back in 1921, a young engineer by the name of Joseph Strauss saw something that nobody else could see. Again, quite obviously suffering from mental illness. Joseph Struss saw the longest two-span suspension bridge in the world, stretching over the most hazardous piece of water in the world - the Golden Gate Straits. He even was insane enough to envision this bridge being painted in a color that would have to be invented specially - international orange. Fifteen years of laughter, ridicule, doubt and sheer-bloody-mindedness later, the Golden Gate Bridge was opened to traffic on May 27 1937. It is widely held to be one of the most beautiful examples of bridge engineering in the world.

Since everybody else can now see what only Joeph Strauss could once see, the man was obviously cured.

According to the miedical profession, seeing things that are not there is a sign that you are suffering from mental illness. Consider this though - all human progress can be attributed to human beings inventing new things. The word 'invent' is defined as to produce or contrive (something previously unknown) by the use of ingenuity or imagination (Free Online Dictionary).

Since producing something previously unknown involves seeing something that isn't there, it follows that - according to the diagnostic tools used in the medical profession - all inventors suffer from mental illness.

Could this really be true? Could it really be that the people on whom humanity depends for progress are all mentally ill?

Or isn't it more likely that we need to redefine our attitude to mental illness, and recognise that the ability to think differently is actually not a bad thing?

500 miles today, 100 of them stuck in very heavy traffic around Paris after taking several wrong turns. That's the navigation part of my Dakar screwed then - I really need to work on this. That said, trying to consult a 1:250000 scale map to figure out what the next turn should be is probably always going to end in failure.

I made it as far as Mende - about 100km North of Millau. I could have hit Millau tonight, but it would be dark and I want to see the bridge in the light - it truly is a thing of beauty. This is approximately the halfway point of this particular trip, and I am bearing up pretty well. 12 hours in the saddle today, and my roadcraft was all but done by the time I was finished. It's the trams that do it - 300-tonnes of silent trauma, running along sticky rails used to trap motorcycles the way that a spider traps flies. In fact, tram rails are the road equivalent of ruts - they were invented by somebody who dislikes bikers, I am sure of it.

I see something that isn't there. I see me at Lac Rose (The Pink Lake) in Senegal - the finishing line for the Dakar Rally. I see my finishers medal. I see The Missus breathing a sigh of relief that it's over, and then start to look horrified when she imagines what will be next - like that bull run thing in Spain.

This week was all about testing my stamina and my general level of bike-fitness. by Saturday, I will have done nearly 2,000 miles of riding - with about 300 of those off-road. Not quite up t the same standars as a Dakar week but if I couldnt physically deal with it then I'd have to be questioning whether or not I can be ready for Dakar in 2009.

As it is, I am bearing up very well indeed. 2009 Dakar here we come.

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