Mental, intellectual or for that matter spiritual practices are not merely things people can choose to do, but they alter in fact the physical make up of the brain itself.
To people who are familiar with modern data on how the brain works, this should not be a surprise, but it is nonetheless easily forgotten. People who have practiced logical, rational thinking are in a very concrete way better equipped to reason. Similarly, people who practice meditation do develop areas of the brain that remain underdeveloped among those who do not practice.