Moaning taxi drivers, complaining old ladies and witless jobsworths – all are a source of mind-numbing tedium for motivational speaker Adrian Webster.

The former Bristol policeman decided on a career change when he faced a crowd of angry rioters during the early 1980s.

He said this frightening event, and others during his police career, made him realise that human behaviour becomes conditioned by experience, but that it can be changed.

Webster's talk on how to be a sales predator began by throwing the human condition into sharp relief. Comparing the 46-million-year-old earth to a 46-year-old woman, he says the average human life is equivalent to 44.4 seconds.

“We humans don't matter,” he said, “that's the first thing to realise.”

The number of people who had made a real impact on history is miniscule, he said, listing only Martin Luther King, John Lennon and Mahatma Gandhi.

But, he asked, why was it that television and newspapers devote acres of space to the people that gripe and moan? Webster said this apparently harmless mind-numbing pollution was a danger because it became absorbed by our subconscious minds where it stayed to shape negative ideas about the world.

Webster said that we allowed other people's gripes to prevent us achieving our own dreams and goals. “Even if you don't make fat city, you will find a town called dignity,” he told his audience at the Biba conference.

His message was: “At least on your deathbed you can say ‘I gave it a try'.”