Buffett - one of the most successful investors ever - hit the headlines in July when he launched a campaign with Bill and Melinda Gates, urging billionaires to give at least half their fortune to charity.
He is leading by example, pledging to donate 99 per cent of his estimated net worth of $62bn (£38bn).
But the Oracle of Omaha is not just a philanthropist. His financial insight is hugely respected: he warned as early as 2003 that credit derivatives were "financial weapons of mass destruction".
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