John Kay

Tailgaters think the view that their behaviour is dumb is based on a purely theoretical analysis, which is refuted by the tailgater’s practical experience. And so the culture of self-confident, self-congratulatory tailgaters perpetuates itself.

All our experience of the development of information technology starts from what the customer might want rather than what the technology might do.

Maintain a clear sense of long-term objectives but acknowledge the limits on your day-to-day actions.

Three simple rules – pay less, diversify more, and be contrarian – will serve almost everyone well who invests.

Think probabilities and be detached. It’s hard advice to follow. That is why the financial services industry is better off than its customers.

The return on your portfolio is the aggregate of the returns on individual securities: the risk on your portfolio is not the aggregate of the risk of individual securities. With the aid of diversification you can earn more return with less risk.

Having seen off the taxman, you must see off the sharks of the financial services industry.

The decline of GM is as instructive as its rise. The challenge of how to reconcile professional management with a culture of innovation remains for ever a central issue for management thinkers.

When the future arrived in 2007, we learnt that others had febezzled from us on a massive scale. And that we had also febezzled from ourselves.

Diversification is a matter of judgment not statistics. A model will tell you only what you have already told the model and can never replace, though it can enhance, an understanding of market psychology and the factors that make for successful business.