They have been placed by the Chartered Institute for Securities & Investment (CISI), which has the subsidiary headline ‘integrity matters’.

You might think it slightly ironic some of these ads are going to run at Bank and Canary Wharf underground tube stations in London – depending on your view of who, or what, caused the financial meltdown five years ago. It this a case of too little, too late, or a welcome reminder?

I do not subscribe to the view the entire crisis can be laid at the feet of the likes of Bob Diamond from Barclays, Fred Goodwin at RBS, or even Dick Fuld at Lehmans.

It suits politicians, and many of us, to think we could blame the crisis on one or two individuals or organisations, because it implicitly makes us feel we have worked out who caused the problem, and we can then find an easy solution.

But we have not identified the causes of the global collapse, and we never truly will. We are rewriting history, pulling together various strands to create a coherent explanation.

Fred Goodwin may well have been an over-ambitious boss who dominated his board, but can he be singularly blamed for forcing RBS to buy ABN AMRO for too much at the top of the market?

Surely all those external, well-informed shareholders could have just voted against the decision?

Why did Lehmans go down, rather than any of the other investment banks which were doing much the same thing? Was it Gordon Brown and Tony Blair’s fault Lloyds was forced to take over HBOS? Who is to blame for the Co-op taking over the Britannia building society? Was it Robert Peston’s fault there was a run on Northern Rock?

Your guess, or informed view, if you like, is as good as mine on any of these issues.
The best explanation I have heard blames it all on Richard Nixon – always handy as he is long dead.

The argument goes he encouraged Congress to abandoned fiscal prudence to help him fund the end of the Vietnam War – as it turned out, successfully.

This was the first example – post World War II – of the sustained monetary expansion that has gone on ever since. And what happens when there is too much money sloshing around? It goes into risky assets and creates bubbles.

Whether you believe that explanation or not, I do not think it is the key issue here, but the CISI has nailed it for me. The issue is integrity.

Well done to the Institute for reminding us that the answer and the solution all derive from that one simple word.

Lawrence Gosling is editorial director of Incisive Media. His views are his own, any comments to him at lawrencegosling1@gmail.com