Be-suited man rides an old-fashioned bicycle across London Bridge.

+ Should cities pay more attention to what might make its residents, workers and visitors smile?

How do we decide what we like and what we choose? Many will say – or like to think – that it is our heads. We are rational.

I disagree.

I think most decisions are made in our hearts or by our gut instincts. Then we may use our heads to post-rationalise. People will do something, or buy something, if it gives them the 'grin-factor'.

As usual, I turn to examples in transport. Walking makes me smile – even more so on a sunny Spring day – but actually in any weather. Striding past a line of queuing traffic is an added bonus. Recent developments in London, where I live, like the removal of pedestrian guardrails so that we are no longer corralled into pens on traffic islands, just makes the walking experience better. Outside our offices the traffic lights have been replaced by zebra crossings which has transformed the junction making it a happier and more relaxed environment.

And there are other examples. I think part of the appeal of London's Barclays Cycle Hire scheme is the freedom that it brings – a freedom that many associate with childhood. You pick up a bike, you cycle to where you want to go, and you leave the bike – no worries about locking up your valuable possessions, you just dock the bike and off you go. It is like the days when you could just leave your bike outside the sweet shop and not worry about it.

Plug-in vehicles provide another example – the turn of a key, the silence of the car and the way it pulls away remind us of a simpler time. They are quality, high performance vehicles, but they have a simplicity and a “future-feel” that appeals.

And a final example, the Heathrow T5 Personal Rapid Transit system. Pods run on guideways and are both simple and futuristic at the same time. A winning combination that brings out the grin-factor.

So should cities look more at what might make its residents, its workers and its visitors smile? Potential urban policies are assessed in many ways and against many factors. Maybe the question “will it make people smile?” should also be asked?