It is one of those magical Dhaka scenes. We are trundling along in a rickshaw down small and crooked lanes. It is night, and light bulbs glow under each rickshaw - miniature moons suspended in the darkness. A warm breeze blows in our faces. All around the sights of nighttime, Dhaka backstreets crowd in on us.

The orange sparks from a welder's torch flare up in a mechanic's shop to our left as the workers crouch round a battered piece of old metal. On our right, a group of old bearded men sit discussing life in a homoeopathist's waiting room where the brown jars glow dully under the bright strip lighting. Pale yellow walls draw the visitors in, suggesting homeliness and calm.

There is the music of rickshaw bells - the traffic, for once a long way away, hidden in the folds of darkness. We pass fabric shops where there are more assistants than customers and CD shops blaring out the latest techno Bhangra music. Women and men emerge from the shadows and slip by almost unnoticed. Occasionally one of them catches sight of this foreigner and a look of momentary surprise travels briefly across their face before they too are lost to the past.

My friend N and I are talking. It's one of those long conversations in which we try to discover each other's culture. We have talked before about our different perspectives on arranged marriages, the rituals of death, the joys and perils of childhood. Tonight though we touch on two more of these topics that delight and contain, for me, the whole point of all this travel and exploration, this journey towards experience.

He tells me how he goes home to visit his family in Rajshahi once a month. He is a college lecturer - a man of knowledge, as we like to say here, a man who commands respect. In fact it surprises me how often I myself am introduced or addressed as a learned consultant. This conjures up an image of a mediaeval scholar, candle in hand, poring over a manuscript that threatens to turn to dust in my fingers.

Despite this great erudition, when N visits his mother at home, everything changes. There he is no longer a 40-year old pillar of the educational community - he is merely a son, and that brings with it a whole new set of norms and rules. He tells me that if his mother instructs him to come home at 9pm, then he does so. If he arrives home late, he is quite naturally reprimanded. This surprises me - surely at his stage in life, he is no longer expects to be rebuked? Why doesn't he tell his mother not to interfere? Why not have a frank exchange of views, clear the air?