Strong functions absorb experience on a wide scale – through them we have greater subjectivity, as they help us form a more complete picture of the world. Meanwhile, Weak functions absorb little experience, often limiting themselves to what we have personally encountered – through them we often feel uncertainty and find it difficult to see things through the eyes of others.
To determine strong and weak functions, it is important to look at how widely a person possesses information; do they only describe their own experience, or do they reason from the standpoint of other people, interpreting their perception of the world. In other words, through strong functions, we can hear notes of confidence not only in how a person themselves views things, but also confidence in their knowledge of how others think and why they arrive at certain conclusions.
The strong functions include the Leading (1), Creative (2), Ignoring (7) and Demonstrative (8) functions. The weak functions include Role (3), Vulnerable (4), Suggestive (5) and Mobilizing (6). These function properties are the basis for dividing types into two pair of traits: Intuitive/Sensing and Ethical/Logical.
Intuitive are types with strong Intuition and weak Sensing, while Sensing are types with strong Sensing and weak Intuition.
In turn, Ethical are types with strong Ethics and weak Logic, while Logical are types with strong Logic and weak Ethics.