Because they deviate on nearly every axis simultaneously. Most heresies are errors of emphasis or precision within a recognizably Christian framework. Arianism gets the Trinity wrong but preserves creation theology, scripture, and ecclesial structure. Manichaeism and Marcionism introduce alternative cosmologies, alternative scriptures, and alternative institutional structures. They are not adjusting one doctrine; they are replacing the entire system. That breadth of deviation is what the radar chart makes visible.
A legitimate objection, but Manichaeism arguably arose as a distinct regional form of Christianity in third-century Mesopotamia and Iran. Mani consistently called himself "apostle of Jesus Christ," used the Pauline corpus and the Diatessaron, and his church actively debated other Christians over who represented the authentic norm. Augustine had been a Manichaean Hearer before his conversion and treated it as a Christian heresy. Its inclusion here follows the patristic classification and the case for Manichaean Christian identity. Its scores reflect the magnitude of institutional and doctrinal departure, even if the self-understanding was reformist rather than supersessionist.
They are opposite errors, one over-dividing Christ's natures and the other over-unifying them, but both produce comparable downstream consequences. Each compromises the soteriological exchange, each generated lasting schisms, and each was condemned by ecumenical councils with similar levels of severity. The radar chart captures consequences and formal condemnation, not the direction of the error. Their profiles are similar in magnitude but differ in shape: Nestorianism scores 7 on Christology versus Monophysitism's 6, reflecting scholarly reassessment of Nestorius (the dispute was largely a philosophical impasse over terminology) and the ambiguity around Eutyches's actual views. Monophysitism scores slightly higher on Ecclesiology (4 vs. 3) because the resulting schism with the Oriental Orthodox churches proved more durable.
Very seriously, but the Church's concern with Montanism was primarily disciplinary and ecclesiological, not doctrinal. Montanists were broadly orthodox on the Trinity, Christology, creation, and soteriology. Their errors clustered around prophetic authority, rigorism, and the claim that the Paraclete was delivering new binding revelation. The tool captures this: Montanism scores 7 on Ecclesiology and 6 on Scriptural Continuity, but near zero on the theological axes. A low composite score does not mean a heresy was not dangerous. It means the danger was concentrated rather than systemic.
Pelagianism is the most concentrated heresy in the dataset. It scores 10 on Soteriology because it directly contradicts the doctrine of grace as defined at Carthage (418) and Orange (529). But Pelagius affirmed the Nicene Creed, accepted the canonical scriptures, worked within the Church's institutional structure, and held an orthodox cosmology. His error was deep but narrow. The composite score reflects breadth of deviation; the individual axis score reflects depth. Both matter, which is why the tool shows both.
Docetism is better understood as a Christological tendency than a unified movement. It appears in various Gnostic systems, in Marcion, and in other contexts. It is treated here as a standalone entry because the patristic sources, particularly Ignatius and Irenaeus, address it as a distinct claim: that Christ's humanity was apparent rather than real. Scoring it separately isolates the consequences of that claim across all six axes, rather than burying it within whichever movement happened to adopt it.
Eschatological questions were rarely the subject of formal conciliar condemnation in the period covered here. Montanist millenarianism and Origenist universalism were controversial, but the councils did not produce definitive doctrinal boundaries on eschatology comparable to those on the Trinity, Christology, or soteriology. Adding an eschatological axis would produce mostly zeros with a few low scores, contributing noise rather than differentiation.
Radar charts are often criticized because the area of the polygon can mislead. It changes depending on which axes are adjacent, and the eye tends to read area as magnitude. These are fair objections. The radar chart is used here because it communicates the shape of each heresy's deviation at a glance, which a bar chart or table cannot. A heresy that scores high on two axes looks visibly different from one that scores moderately across all six. The composite ranking in the sidebar provides a single-number summary for those who prefer not to rely on the polygon.
Not fully. Trinitarian errors often produce Christological consequences, and Christological errors frequently cascade into soteriology. This covariance is real and acknowledged. The axes measure distinct doctrinal domains as defined by the councils, not statistically independent variables. Some degree of covariance is inherent in the subject matter. The Fathers themselves argued that getting the Trinity wrong meant getting the Incarnation wrong, which meant getting salvation wrong. The tool does not claim orthogonality; it claims that each axis captures a domain the councils treated as separately addressable.
Strictly speaking, no. The scores are ordinal: a 6 represents a greater deviation than a 4, but the interval between them is not necessarily equal to the interval between 2 and 4. Averaging assumes interval-level data, which this is not. The composite is offered as a rough summary for comparison, not as a precise measurement. The weighting controls make this explicit: changing the weights changes the composite, which reminds the user that the number is constructed rather than discovered. The individual axis scores and the radar chart shape are more informative than the average alone.
Probably not exactly, and that is a limitation. The rubric anchors (0, 2, 4, 6, 8, 10) are defined with reference to conciliar outcomes, but placing a given heresy at 7 versus 8 on a given axis involves interpretive judgment. The score reasoning for each data point is provided so the user can evaluate and disagree with individual placements. A more rigorous version of this project would involve multiple independent raters and a formal inter-rater reliability analysis. This version is a single-author interpretive framework, not a validated instrument.
Yes. If two high-scoring axes are adjacent, the polygon bulges outward and looks larger than if those same scores were on opposite sides of the chart. The current ordering follows a rough logic: doctrine of God, doctrine of Christ, doctrine of salvation, doctrine of creation, doctrine of the Church, doctrine of scripture. Rearranging the axes would change the visual impression without changing the underlying data. The composite score and individual axis bars are unaffected by axis ordering, which is one reason both are provided alongside the chart.