And Mr Poortman argued that corruption acted as a catalyst for the global financial crisis - because ratings agencies had a conflict of interest and "turned a blind eye to high levels of risk", something he said was "a form of corruption".

BBC: Corruption 'stifling economies'

As long as overall numbers stay within planned levels, it may well turn a blind eye to universities that decide to increase student numbers taking the most popular courses.

ECONOMIST: The birth pangs of a market in higher education

He added that in addressing climate change, the international community must not "turn a blind eye to historical responsibilities, per capita emissions and different levels of development".

BBC: President Obama warns leaders over climate summit deal

Despite being long-established, participation levels in Britain are very low, said Mr Troy who was born blind.

BBC: Paralympics legacy: 'We have to tell people they can'

Secular bull markets, typically, start from levels of valuation that are extremely low and associated with despair, not blind-optimism.

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