Sönke Ahrens

Yes, a certain intellectual capacity helps to get into academia, and if you struggle severely with an IQ test, it is likely that you will struggle to solve academic problems, too. But once you are in, a superior IQ will neither help you to distinguish yourself nor protect you from failure. What does make a significant difference along the whole intelligence spectrum is something else: how much self-discipline or self-control one uses to approach the tasks at hand (Duckworth and Seligman, 2005; Tangney, Baumeister, and Boone, 2004).

Willpower is, as far as we know today,[2] a limited resource that depletes quickly and is also not that much up for improvement over the long term (Baumeister, Bratslavsky, Muraven, and Tice, 1998; Muraven, Tice, and Baumeister, 1998; Schmeichel, Vohs, and Baumeister, 2003; Moller, 2006).

Luckily, this is not the whole story. We know today that self-control and self-discipline have much more to do with our environment than with ourselves (cf. Thaler, 2015, ch. 2) – and the environment can be changed.