The development of expertise is a fascinating area of cognitive science. I recently read a well-written story in Scientific American (August 2006, Volume 295, Number 2) on this topic entitled "The Expert Mind" by Philip E. Ross. Unlike the commonly held belief that experts have some innate talent that enables them to advanced knowledge and skills in a particular field (e.g. physics, history, health care, sports, music, chess), expertise is acquired through hard work and practice (practice, practice, and more practice). For most individuals of average intelligence, expertise in any field can be rapidly acquired in childhood and early adulthood. Undoubtedly individuals acquire knowledge and skills in some fields more easily than others - perhaps due to their personal learning style, positive feedback from mentors/teachers/parents, as well as social conditioning. But expertise in any field is primarily acquired through years of study and taking on challenges that are just beyond one's current level of knowledge/skill (known as the zone of proximal development).
The implications are important because it means that expertise is acquired through purposeful activity - and it is not something that is innately inherent. Or is it? What do you think?