On July 7th, 2005, near Edgware Road in London, shortly before 9am, I sat on a train, listening to my music on an iAudio M3L (I was very late to the iPod party), on my way to my Accenture job. It was summer, but the weather was not particularly sunny. Typical London grey. I don't remember what I was thinking about, but it was probably something trivial.

Suddenly, there was, first, a flash. The light came before the sound. My vision went black, and simultaneously a bright light started at the centre of my vision and expanded outwards. It looked like those cartoon drawings of explosions, but bright and, soon, loud. Not a weighty, ponderous sound, more like the bass-less sound of a firearm (in real life, not in the movies). Like a very loud TACK.

Thick black smoke poured through the open windows at either end of the tube carriage I was in and quickly filled it. I sat frozen, incapable of moving, not even to pull the headphones out of my ears. Only one thought looped through my head, over and over and over again, endlessly:

This was a bomb. This was obviously a bomb. There could be another bomb. If the other bomb was in this carriage, I would be dead before I knew it.

Before that day, I never understood the expression "paralysed by fear". It was something I'd read and dismissed as an image. On July 7th, 2005, I experienced it directly. For what felt like an eternity (but I think was about 2 minutes) the only thing my brain could do was repeat that same stream of thought over and over again endlessly. There seemed to be nothing else to do or think in the universe. I was maybe about to die and that was all that mattered. I didn't even look around the carriage to see how other people were reacting. I was in my own little world, frozen, paralysed.

How did I get out of it? Somehow, I noticed some movement to my side. People were trying to pry open the doors of the train, to let some of the smoke out, to let some air in. I felt an impulse to help. A new thought appeared: I am a mentally balanced, healthy young man. I should be one of those people who can help others in this situation, not just a passive, helpless observer. I can help: I have a backpack which I can stick into the doors to keep them partly open.

The paralysis drained away. I stood up, went to the door, and as the others held them open, shoved my backpack in the opening. They released their grip and the doors stayed partially open, letting the ugly smoke out and the marginally better air from the tube tunnels in.

Now that I was standing, I pulled my headphones out. But the music continued playing in my head. It was a hypnotic, great track by James Holden. You can listen to it here, while you read the rest of this article. For the forty-five minutes that we were all stuck in this carriage with our fears, the music never stopped. I like to think that some part of my brain knew that I needed the soothing that the music provided.

I remember some parts from those 45 minutes. Mostly, I remember having to rise above the fear of there being another bomb. I remember looking around and seeing that this fear was in every face, in every word that every person said, and at the same time, it was anathema, unspeakable, and for forty-five minutes not a single of the 40 people in that carriage put that fear into words.

I remember a young woman who stood next to me and tried to make conversation, probably to reassure herself that all was normal. I remember that I could not give her that reassurance. I was fighting my own demon, and I had no energy to spare on small talk, which takes effort from me even in normal social situations. I could tell she needed it, but I could not give it. Eventually she found someone else to try to talk to.

I don't remember what was discussed by people in the train, but I remember there was a concerted, deliberate effort to not think of what this obviously was. Everyone knew it was obviously a bomb. But the awful consequence that rode on that thought, the possibility of there being another bomb right here, right now, was unthinkable, and so the obvious truth was banished. I even convinced myself, for a while, that it could be something else.

It was hard work, this self-delusion, when the minutes were punctuated by the nearby screams of the wounded and dying. Six people died there at Edgware Road, metres away. Fifty-six, including the four bombers, across the tube network. Several dozens more lived with serious injuries, their life probably changed forever. But for forty-five minutes, forty uninjured commuters managed the feat of convincing themselves that this was anything but a bomb. I think the favourite theory was an electrical explosion, until the driver walked through the carriage.

He came to perform the impossible task of reassuring us and to let us know what was next. The reassurance was honest, if not very effective. Asked if it could be an electrical explosion, he answered, "I don't know what this was, and I don't want to make up any theories, but I know in 18 years of working here I've never seen anything like this." He stopped short of declaring the obvious.

However, by then, the self-delusion was in full effect. To give you an idea of how much we all needed to believe that this was not what it plainly was, one old lady, wrapped up in the reality distortion field, asked the driver if it would be possible to ask people in the neighbouring carriages to stop screaming, as it was very unnerving.

"Madam, some of these people are dying," was the driver's response, ending that conversation.

It's easy to think that woman was insensitive. She merely expressed, in an absurd way, the belief to which we were all clinging to. She probably regrets asking that awful question, to this day. But she shouldn't. She was a symptom of a group behaviour, not a cause of it.

Eventually, we were allowed out of the train. Our train was not actually damaged (other than the front), the bomb had been on the oncoming train. As the driver later put it in this BBC interview, we were incredibly lucky. Had the bomb exploded ten seconds later, it would have taken out one of our carriages too - maybe the one I was sitting on. I owe my life to a terrorist's inept planning.

Our train had stopped going forward in part because the roof of the other train was on our tracks, ripped out by the blast. Both had continued moving forwards, coming to rest alongside each other. So at one point, still inside our train, we had to pass, to our right, the carriage where the blast had happened. The driver advised us not to look to the right.

In most other situations, I might have disobeyed. I am naturally curious. I need to observe. I want to. This time, I did what I was told. Somewhere inside, I knew that I would have enough emotional baggage to deal with without throwing in pictures of dying people and mutilated, burnt bodies. We got out of the carriage, walked along the tracks, and came out of the station. There was no one waiting to shuffle us towards ambulances, care workers, or anything, and that's ok - we weren't injured at all, at least physically. They should probably have taken names, to offer psychological counselling later, but they had other things to worry about.

The only signs of the death happening below were two people, wrapped in the thick bandages which are used on gravely burnt people. They were covered from head to toe. Did they live or not? I don't know. They were sitting alone, abandoned, motionless, leaning against a wall. Chaos reigned outside, police, ambulances, people, crowds, cars, buses, all jumbled up.

I managed to call my parents just before the phone network broke down. "There's been some kind of bombing in London. I'm ok. I'm getting away from the crowds."

And I did. As my mind started working again (or so I thought), my one thought, resuming from below-ground, was to stay away from crowds. There might be another bomb. I walked west, and ended up near some office buildings. There were bench-like wooden structures there. I sat down on one and I cried for ten whole minutes.

I needed to let the emotions out. I was too full, bursting.

Eventually, I ran out of tears. Insanely enough, I decided to make my way to work, on the other side of town, while avoiding public transports. I walked all the way to the centre of Hyde Park. There, I sat on a bench and cried some more. Someone walked past me and, excited and scared, said "there's been a bombing!" "Yeah, I know..." I said weakly as he walked away.

I continued my wandering, aiming roughly in the right direction. I felt clear-headed, but in hindsight my brain was clearly not quite right yet. I was sleep-walking, moving in automatic mode. The obvious thing to do was to go home, but the default was to go to work. I was finally jolted awake when a huge truck stopped next to me. I flinched away - imagine if there was a bomb in that! - and then noticed some soldiers with big machine guns pulling up concrete fence-slabs into the road. I heard an elderly gentleman ask one of the soldiers what was going on, and the soldier replied that this was the US embassy.

The US embassy!

Somehow, wandering randomly through London in a general west-to-east direction, trying to avoid dangerous crowds, I had managed to find myself in probably the most risky place to be a few hours after the bombings. That woke me up. I made my way home.

On the way, I remember seeing a bus crammed with people. It stopped next to me, and I took some steps away from it. Insane, I thought. After what just happened? But for most people, this was just an annoying travel disruption, I guess.

I got home. A friend came to visit to make sure I was alright (thanks Andy!). I was. This was a Thursday, and Friday was declared a day off. I stayed out of public transports for the weekend. On Monday, I had to get to work, but, although I felt no sense of panic, I decided to travel at 6am to make it less likely that I would connect tube travel with fear. The tube was mostly empty at that time. This would not be a popular hour for a bombing.

Over time, I got used to the tube again. Now, I feel no fear - almost. Every once in a while, very rarely (once or twice a year), I will spot someone who looks suspicious, with a bag that could contain a bomb, in my carriage. Sometimes, that is followed by a wave of fear. I can control it. It doesn't show on my face or in the tone of my voice. But at the next stop, I get off and wait for the next train. Just in case.

Throughout that summer, my second year in Accenture I had been mildly discontented. I felt that my job was a little boring, but I kind of accepted that. It was a new project - my second project - so it wasn't so bad. And yet, it was during that summer that I started looking for a new job. There was something about the idea that I might have died in a grey train full of grey commuters, having not truly lived, that I could not stand.

Over the next year, I looked for jobs in banks and other consultancies, but they all seemed even worse than the job I had. I started writing fiction again. I read self-improvement books like "Seven Habits" and prepared a "mission statement" for myself, to figure out what it was that I wanted. Eventually, in my third year there, I started to think of starting my own business. Yes, that seemed more interesting.

Then, one of my best friends got in touch with me with this idea to build this business that would make money. The rest of the story can be found scattered around the internet, on this blog and others. Today, in December 2011, six and a half years later, if I were to die in a train carriage tomorrow - well, I would still feel unfulfilled (there's a lot I still want to achieve, of course) but a hell of a lot less so than if the bomb had exploded 10 or 20 seconds later, that morning on July 7th, 2005.

Did this event change my life?

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