Introverted sensing is associated with the ability to internalize sensations and to experience them in full detail.
Introverted sensing focuses on tangible, direct (because external) connections (because introverted) between processes (because dynamic) happening in one time, i.e. the physical/sensual experience of interactions between objects. This leads to an awareness of internal tangible physical states and how various physical fluctuations or substances are directly transferred between objects, such as motion, temperature, or dirtiness. The awareness of these tangible physical processes consequently leads to an awareness of health, or an optimum balance with one's environment. The individual physical reaction to concrete surroundings is main way we perceive and define aesthetics, comfort, convenience, and pleasure.
In contrast to , is related to following one's own needs instead of focusing on some externally-driven conception of what is necessary to acquire or achieve. So, whereas ego types feel capable to evaluate how justified others' preferences are, ego types will try to adjust to them in any way possible (given that it does not extremely affect their own comfort), wishing to minimize conflict.
In contrast to , Si is about direct interaction and unity (or discord) with one's surroundings, rather than abstract process and causal links.
1. Introverted sensing
SLIs are naturally good at knowing what kinds of activities and stimuli will produce which sensations and physical states in themselves and the people around them. They are highly sensitive to sensations of internal discomfort and dissonance, or when someone or something is aesthetically out of place. They usually take quick action to remove the discomfort, dissonance, or misplacement so that things "feel right." They are attracted to material (concrete) objects which produce the "right" sensations and physical states, such as stereo systems which produce the best sounds or clothes that produce the best feelings either through their pleasant texture and ease of use or through their aesthetic appeal. They dislike it when others deny them of pleasurable material objects and can get quite possessive and territorial when claiming or re-claiming them.
SLIs are skilled at recognizing and remembering their own and others' internal physical states and at imagining how different things would affect that state. When analyzing the behavior of themselves and others, they focus on these physical states and see them as determining much of a person's actions. They prefer to keep their lifestyle and living space simple and to avoid excessive, gaudy possessions and excessively complex living habits and duties. SLIs encourage those they care about to take the time to experience pleasurable and soothing sensations, avoid getting caught up in the hustle and bustle of everyday life, and to listen to their bodies and their sincere inner desires. They can be concerned with their own health and those they know.
SLIs are drawn to situations which allow them to maximize these physical states and like to dwell on soothing, pleasurable sensations, or the enjoyment of physical motion. They often seek physical and manual involvement in work activities. SLIs prefer to get involved in business projects rather than sit back and let things happen on their own (weak Ni too). SLIs are adept at portraying excitement and disgust through their physical gestures.