E01¶


Research	R0050 — Journalism Disciplines
Run	2026-03-31-02
Query	Q002
Source	SRC05
Evidence	SRC05-E01
Type	Factual

FTA contributes Boolean logic gates for causal reasoning — a novel structural approach

URL: https://en.wikipedia.org/wiki/Fault_tree_analysis

Extract¶

FTA uses a top-down deductive approach: start with an undesired event (top event) and decompose it into the logical combinations of causes using AND/OR gates.

Key structural features: - AND gates: All sub-events must occur for the parent event - OR gates: Any sub-event is sufficient for the parent event - Quantitative analysis: Probability of the top event is calculated from component probabilities using Boolean algebra

Novel concept: FTA's Boolean logic decomposition of causal chains is structurally distinct from anything in the nine reference frameworks. While Chamberlin/Platt generates competing hypotheses and ICD 203 assesses probability, neither uses formal logic gates to map the structural relationships between causes. FTA treats causation as a formal logical structure, not just a probability assessment.

However, FTA is a complementary tool to FMEA rather than a standalone evidence evaluation framework. It analyzes system failure logic rather than evaluating evidence quality.

Relevance to Hypotheses¶

Hypothesis	Relationship	Strength
H1	Supports	Novel logical structure for causal analysis
H2	Partially supports	Novel but narrower contribution than FMEA
H3	Contradicts	Clearly formal methodology

Context¶

FTA and FMEA are often used together — FMEA identifies potential failures bottom-up, FTA analyzes failure propagation top-down. Together they represent a comprehensive safety analysis methodology with structured evidence evaluation at every level.