The outcome of the debate of nature versus nurture is a foregone conclusion. It confused people in the past, but we now know that the problem is an example of confounding. Vaci et al. have published a paper in 2019 in a longitudinal study tracking chess players throughout their careers. And the results showed the importance of numerical intelligence and deliberate practice to master and retain chess skills. Nonlinear interactions between the two suggest that intelligent people benefit more from practice.
The work looked at 90 chess players across their careers – the Elo rating and the number of tournament games played. Three levels of intelligence – verbal, figural and numerical – were followed but found that the numerical has the highest correlation to the performance.
The nonlinearity of behaviour means people of different ages climbed up the rating ladder differently. For 20-year olds, players with an IQ of 120 benefited more from the same amount of practice than ones with IQs of 100 at lower practice regimes. At that stage, more practice of both groups reduced the gap between their performances. At the very high levels of practice, the higher intelligent folks started deviating from others for better performance. The behaviour is represented in the schematic below.
The joint influence of intelligence and practice on skill development throughout the life span: PNAS
