How INTJs can develop
The development of personality occurs in phases throughout life. For someone who is young, the main task is to develop use of their preferred mental functions. As one matures, however, and approaches midlife, there is often a need to develop greater comfort with using your non-preferences. This can help you increase your performance at work, and increase your ability to deal with different people and circumstances.
As with all types, an INTJ can achieve personal growth by developing those functions that are not fully developed, through actions such as articulating the INTJ's vision, and allowing others to contribute to its development, expressing appreciation for work done, even when it falls short of the INTJ's personal standards, and investigating the facts and documenting them before interpreting what they mean. You may need to consider the impact of your approach and ideas on other people's feelings, looking for and acknowledging positive contributions and areas of agreement, rather than just seeing flaws and areas of disagreement.
A common theme of development for all types after midlife is individuation. This involves learning to value and develop various "opposites", not just the opposite typological preferences. Through reconciling opposites, your personality becomes more individual and unique, and your personality type may change. You might also reach the stage where your closest personality type is no longer a description of you, but it is merely a part of your personal history.
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