Truly original thought has nothing whatever to do with our genes. In the Seventies Professor Liam Hudson published studies showing that post-doctoral researchers with firsts were actually less successful than those with 2.1s and 2.2s. Given what it takes to get a first, this should not be surprising. You need to please your teachers, enjoy being supervised closely and please the examiners, concentrating on what they want. To do research and succeed as an academic, you need the opposite: think originally, be highly self-motivated rather than craving constant praise and be able to work alone for long periods.
True, trainee accountants with firsts or 2.1s (65 per cent) are more likely than 2.2s or thirds (41 per cent) to pass their accountancy exams. But that does not prove that the ones with better degrees are more likely to get to the top of those professions. Large organisations like the civil service or retailers which have developed ways of picking winners are less concerned with degree class than performance in their in-house psychometric tests. A survey of 254 leading companies showed that 71 per cent thought exam results a poor guide to an individual's abilities at work.
If academic performance does not predict who will become a high achiever, then what does? Contrary to the unceasing torrent of claims for the role of genes, the evidence does not support them. Although studies of identical twins suggest IQ performance is half heritable, there are strong reasons to doubt their validity (see The Gene Illusion, by J Joseph). Even if genes determine IQ to a large extent, people with exceptionally high IQs are no more likely to succeed in their careers than those in the above-average but not-exceptional category (with an IQ around 120). A follow-up study of 400 Americans who had IQs of 150 or more (the average is 100) in childhood did not find that they had unusually successful careers for people of their class and educational background.
If you take the twin studies' findings as valid, they do not show a big role for genes in determining many key skills for high achievement. Some personality traits are heritable, like extroversion and emotionality (40 per cent), but many are not, like sociability (25 per cent). Crucial mental abilities - memory and exam ability (32 per cent), creativity (25 per cent) - are not very heritable.
'He's not very bright' is one of the thickest things a person can say in explaining someone's performance. Most of the time, it means that the person is not very good at the social skills required for career success - Machiavellianism, charm - or is not highly motivated.
One of the strongest crude predictors of getting to the top is a preparedness to hop between jobs. High achievers show less loyalty to companies and make more career changes (likewise, surprise, surprise, such people are also more likely to be sexually unfaithful).
· See Oliver James's books They F*** You Up (£7.99, Bloomsbury) and Britain on the Couch (£8.99, Arrow) for references to studies mentioned here.
