How ISFJs 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 ISFJ can achieve personal growth by developing those functions that are not fully developed, through actions that are much more change oriented. You may need to learn how to 'give things a try' when the outcome is uncertain, develop a long term version that looks beyond existing areas of knowledge, and become more comfortable in dealing with conflict and/or taking control. For example, others may at times find constructive criticism more helpful than just encouragement on its own, and sometimes they may prefer to be given direct instructions rather than invited to express their opinion on every team decision.
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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