Si
Cognitive Functions

Introverted Sensing

Compares the present experience with internally stored experience, details, and stable reference points.

How it processes information

Overview

  1. 01

    Receive present facts and sensory information.

  2. 02

    Compares them with internal reference points, standards, or familiar patterns.

  3. 03

    Identifies continuity, anomalies, and the conditions that support reliability.

Subjective experience

Si · Introverted Sensing

Changes from a familiar baseline may stand out quickly.

Familiar processes and dependable details can provide a sense of stability and efficiency.

Memories often carry specific textures, sequences, or physical experiences.

Si ≠

  • It does not mean that memory must be good.
  • Does not mean being conservative or rejecting innovation.
  • Does not mean that it only deals with details.
  • Does not mean liking all traditions.
Si vs Se

Si interprets the present through internal experience; Se responds more directly to the external reality of the moment.

Current informationExperience comparisonStable reference
1–4

16 Types · Function Stacks

01

Dominant

Often relies naturally on continuity, reliable details, and internal reference points.

02

Auxiliary

Provides facts, precedents, and stable processes that support external organization or care.

03

Tertiary

Provides a sense of familiarity and detailed calibration that may also lead to comfort routines.

04

Inferior

Discomfort, old mistakes, or worries about details may be amplified under stress.

Same function, different types

Si · Across different types

For an ISTJ, Si is often supported by Te, which turns experience into standards and dependable execution.

For an ISFJ, Si is often supported by Fe, which applies remembered details to the needs of people and relationships.

Overuse

Interpersonal Challenges

  • May assume that what worked in the past must still be valid now.
  • May reject an unfamiliar method mainly because it feels uncomfortable.

When out of balance, you may double-check details, physical sensations, or past mistakes, and have difficulty believing that changes are controllable.

Practice

Growth Suggestions

  1. Distinguish between "familiar" and "really more reliable".
  2. Set up small-scale, reversible experiments for new methods.
  3. Record the conditions under which the experience applies, rather than just the conclusion.