Abraham Lincoln’s ringing declaration echoes down the years. His 1863 Gettysburg Address, delivered 160 years ago this Sunday, gave us ‘Government of the people, by the people, for the people’: a clear and simple formulation, it has come to be seen as the very definition of democracy.

But Lincoln was wrong: wrong then and wrong now. Government of the people? Yes indeed, after a fashion. Government for the people? Of course. But government by the people? The advent of social media and almost hourly opinion polling reduces that argument to absurdity, throwing its flaws into sharp relief. For me, a curious incident in which I was involved at St Pancras station recently illustrated this.

Opinion had swung from (almost) riot to second thoughts, to sympathy for the object of our former hatred

I had boarded the last train of the day with a connection to Matlock. Seated in the rearmost carriage and awaiting our train’s departure at 21.02, I heard not the customary final whistle from the platform, but the sound of shouts. ‘Get back!’ came a guard’s voice. Seconds later the door at the end of our carriage slid open and a youngish white man came running down the corridor, an East Midlands Railway attendant in hot pursuit. She raised her voice: ‘You must leave the train!’ Ignoring her, the unwanted passenger sat down towards the other end of my carriage. Two EMR attendants were soon by his seat, insisting he get off. Other passengers in the carriage were agog as the explanation for this ruckus became clear.

It seems that, minutes before our train was due to depart, the man had jumped the ticket barriers, knocking aside the attendant trying to stop him. He had protested that his mobile phone, on which alone his ticket could be accessed, had run out of battery power and died. On being told that without showing a ticket he could not board the train, he had taken the law into his own hands. EMR staff had given chase. Now they were demanding he leave the train and insisting (politely) that we would not be departing the station until he had alighted. But he was standing – or sitting – his ground. He sounded quite well-spoken, not drunk or aggressive, but waving his useless phone.

At this point there was absolutely no sympathy among the 15 or so passengers in our carriage for a fellow threatening to make us all late. Complaining voices were raised. The offender kept insisting he did have a ticket. Scepticism among the other passengers was palpable. Railway staff, meanwhile, were insisting that whether or not he had a ticket his behaviour had disqualified him from travelling. As time ticked by – it was about ten past nine – anger erupted among the passengers. A big fellow tried to recruit others to help manhandle the offender out of the carriage door, and there were murmurs of approval. Others were just shouting: ‘Get off!’ EMR staff were trying to calm people down, but things were getting ugly.

At this point I made my only intervention, advising the militant tendency among us that if there were a violent struggle the railway police would be called and would have to declare an incident and get statements from witnesses, and this would delay us for a great deal longer. Maybe my intervention helped. Calls for a vigilante passenger uprising ceased. But mutterings against the EMR staff were heard. Why didn’t they just pick him up and dump him on the platform?

Then another passenger announced she had a phone charger she thought would work with his smartphone. Why didn’t we bring it back to life? He handed over his phone. There was widespread agreement to this plan: we could surely call his bluff. The phone was plugged in. Railway staff, meanwhile, were making clear the offender must leave, whether or not he had a ticket, but nobody was listening to them. A couple of minutes more elapsed. The sleeping smartphone woke up. The young man did have a valid ticket, after all.

But now the EMR staff’s argument was gaining approval. Someone who sounded knowledgeable said knocking an attendant aside amounted to assault. ‘Call the police’ became the new cry. Presumably the railway staff had already done so, but the transport police took their time. Would they ever come? It was knocking on for 21.20.

And next a new current of opinion surfaced. ‘For heaven’s sake’ – what was all the fuss about? The guy had a valid ticket. The transport police must be hiding. The first stop was Leicester. Why couldn’t they delay dealing with him until Leicester, then we could all get home to bed? I sensed an ‘Oh sod it – let him go – this is making us late’ mood gaining ground. But the railway staff were sticking to their guns.

Then the transport police arrived. A cheer rose from the carriage. Officers approached the culprit calmly and talked to him quietly. Sensing himself on a hiding to nothing, he got up and, accompanied but not manhandled by the police, he left, to further cheers. We pulled out of St Pancras.

Within the space of less than half an hour, opinion among the passengers – let’s call them ‘the people’ – had swung from violent disapproval to (almost) riot, to second thoughts, to sympathy for the object of our former hatred, to irritation with the railway employees and their silly rules, to dissatisfaction with, then wild admiration for, the police, and finally respect and gratitude for the professionalism of the EMR staff. In microcosm and during the space of about 25 minutes, I had observed the erratic movement of the will of the people, and the shallowness and temporary nature of what felt at the time like strong emotions and very decided opinions.

So how about reform of the NHS next, or what to do about social care? Or a ceasefire in Gaza? Or a tax giveaway in the Chancellor’s Autumn Statement? Come off it, Abe. Democracy is government not so much by the people as in negotiation with the people. Governments must, in the end, govern.