Core Cognitive Functions & Traits
Dominant: Introverted Sensing (Si)
Auxiliary: Extraverted Thinking (Te)
ISTJs are the reliable organizers and steady guardians of the MBTI world. Their dominant Si grounds them in tradition and detail, while auxiliary Te drives them to maintain structure and efficiency. ISTJs are practical, responsible, and excel at creating order and consistency, ensuring that systems run smoothly and reliably.
Representative Formula: Bayes' Theorem
Origin: Probability Theory / Statistics
Formula Components
- P(A|B): Probability of A given B (posterior).
- P(B|A): Probability of B given A (likelihood).
- P(A): Probability of A (prior).
- P(B): Probability of B (evidence/normalization).
Rationale for Match
Bayes' Theorem is a natural fit for the ISTJ's logical, evidence-based approach to the world. Just as the theorem updates beliefs based on new evidence, ISTJs use their Si and Te to continually refine their understanding, making careful, data-driven decisions. Their strength lies in their reliability, attention to detail, and ability to build order from the accumulation of facts.