The Mastermind Rational is one of the 16 role variants of the Keirsey Temperament Sorter, a self-assessed personality questionnaire designed to help people better understand themselves. David Keirsey originally described the Mastermind role variant; however, a brief summary of the personality types described by Isabel Myers contributed to its development. Masterminds correlate primarily with the Myers-Briggs type INTJ. They make up about 1% of the population.
Mastermind (role variant) Wikipedia
Masterminds are introspective, logical, rational, pragmatic, clear-headed, directive, and attentive. As strategists, they are better than any other type at brainstorming approaches to situations. Masterminds are capable but not eager leaders, stepping forward only when it becomes obvious to them that they are the best for the job. Strong-willed and very self-assured, they may make this decision quickly, as they tend to make all decisions. But though they are decisive, they are open to new evidence and new ideas, flexible in their planning to accommodate changing situations. They tend to excel at judging the usefulness of ideas and will apply whatever seems most efficient to them in accomplishing their clearly envisioned goals. To Masterminds, what matters is getting it done—but also learning the principles of how to get it done efficiently and well, that is, at a professional level of quality. However, they may not give much thought to the social cost of getting there, "focusing so tightly on their own pursuits [that] they can ignore the points of view and wishes of others."
Masterminds are highly pragmatic, and they will put forth a great deal of time and effort to implement effective ideas. They are driven to solve complex problems and to create organized, decided, and executed solutions. Masterminds tend to make positive statements instead of negative ones, focusing on how to make the organization more efficient in the future rather than dwelling on past mistakes.
Masterminds are also highly theoretical, and one of the more open-minded of the 16 role variants. Before Masterminds adopt a theoretical notion, they insist on researching all the available data and checking the idea against reality. Masterminds are suspicious of theories based on poor research and will discard ideas that cannot be effectively implemented.
As leaders, Masterminds are skilled in contingency planning and entailment organizing, which are directive activities that tell the planner what activities to do and in what order to do them. Once in a position of power, Masterminds are known for their efficiency and willingness to adopt useful ideas.
For illustrative purposes, Keirsey and his son, David M. Keirsey, have identified well-known individuals whose behavior is consistent with a specific type. Unless otherwise noted, the categorization of the individuals below, whether living or dead, as Masterminds is a matter of expert opinion rather than the result of actual testing of the named individual.Ayn Rand
Dwight D. Eisenhower
Ulysses S. Grant