The Ecclesiastical Friction Index

What the EFI Is

The Ecclesiastical Friction Index (EFI) is a dimensionless coefficient, currently set at 0.73, that quantifies the degree to which one denominational severance event increases the velocity and probability of subsequent severance events within the same institutional context.

In plain language: when a seminary loses one denominational approval relationship, the EFI tells you how much faster it will lose the next one. An EFI of 0.73 means each severance event accelerates the rate of the next by 73%. This is what our modeling team describes as "brisk." The word they reached for first was "alarming." We redirected them toward "brisk" for the purposes of this publication.

Derivation Methodology

The EFI was derived from the IMWA's longitudinal dataset of denominational severance events spanning 1517 to the present day. Our analysts began with the Protestant Reformation — which the IMWA considers the original institutional severance event and the one against which all subsequent events are calibrated — and tracked the acceleration pattern of each major subsequent schism, split, departure, and what one dataset entry simply describes as "an unpleasant Tuesday in 1847."

The derivation process involved three stages:

1. Event Identification: Cataloging all documented instances of an institution losing an approval relationship, membership, or affiliated body due to theological disagreement. The dataset contains 14,440 events. The Institute notes that this number is not a coincidence and has opened a separate inquiry.
2. Rate Calculation: For each event, measuring the interval between it and the next event within the same institutional lineage, then computing the ratio of the prior interval to the subsequent interval. A ratio above 1.0 indicates acceleration.
3. Coefficient Averaging: Averaging these ratios across the full dataset, weighted by institutional size, theological distance traveled, and what our senior fellows describe as "the general ambient level of denominational tension in the period." The result was 0.73. We have checked this number many times. It remains 0.73.

How the EFI Works in Practice

Applied to a specific institution, the EFI compounds as follows. Assume an institution begins with a baseline severance rate of 1.00 events per year:

Note: These intervals represent the expected time between events under EFI compounding. Actual intervals may vary based on the institution's Theological Disagreement Coefficient, leadership stability, and whether anyone has read this table.

The Theological Disagreement Coefficient

The EFI should not be confused with the Theological Disagreement Coefficient (TDC), though they are related. The TDC measures the ambient level of doctrinal tension within a given institutional ecosystem at a given moment. The current TDC for American Protestant Christianity is also 0.73.

The Institute acknowledges that the EFI and TDC are currently the same number. This is not a methodological error. This is a coincidence that our senior fellows describe as "either deeply meaningful or deeply meaningless, and we have not yet determined which." A working group has been convened. The working group's preliminary findings are that the number 0.73 appears more often than chance would predict. The working group's secondary finding is that this observation may itself be evidence of something. The working group meets Thursdays.

Limitations and Caveats

The IMWA presents the EFI with full transparency about its limitations, which are as follows:

• The coefficient assumes a constant relationship between severance events. In practice, some institutions develop institutional antibodies to severance — a resilience the EFI cannot model and which the IMWA finds suspicious.
• The EFI does not account for reunification events, of which there have been seventeen since 1517, none of which meaningfully reversed the trajectory of any dataset entry we were prepared to count.
• The derivation period begins in 1517, which means the EFI is, in some sense, Martin Luther's fault. The IMWA does not assign moral blame. The IMWA assigns coefficients.