Numbers encode and unlock reality. They connect the visual and material worlds with the realm of ideas and function as fundamental epistemic tools for organising and communicating belief systems and worldviews.

Numerical frameworks shape mythology, theology, and demonology; cosmo- and astrological concepts; ritual, magic, and mantic practices; geometric and arithmetic figures; and, not least, the design of objects and spaces. Across these domains, numbers operate as ordering principles mediating between perception, knowledge, and value.

Focusing exemplarily on the number 7, the workshop brings together concise case studies that examine the numerical and numerological structure of abstract concepts as well as visual and material phenomena in Graeco-Roman antiquity and beyond. The number 7 will be treated as a heuristic and analytical Grundbegriff: a basic conceptual tool through which societies articulate cosmic order, social organisation, political authority, ritual sequence, epistemic practices, and philosophical thought.

The aim is to shed light on the age-old impulse to translate the world into numbers and uncover meaning in numerical codes – a notion that continues to reappear in successive metamorphoses from antiquity through medieval and early modern traditions to the digital media cultures of the present.

In order to obtain a common ground of discussion, we kindly ask to refrain from free-floating numerological speculations.

Inspiring papers will be suggested for submission to the peer-reviewed journal "Zeitschrift für archäologische Aufklärung".

PROGRAMME (provisional)

THURSDAY, 16 July 2026

13–19.30: Session 1

Introduction

Elisa Bernard (Classical Archaeology, Erlangen):
7 Kings, 7 Hills, 7 Pignora Imperii: Varro, Servius, and the Heptadic Architecture of Roman Legitimacy in Times of Crisis

Gabriele De Anna (Philosophy, Udine/Bamberg):
Why is there exactly seven deadly sins according to St. Thomas?

Nikolaus Dietrich (Klassische Archäologie, Heidelberg):
Quantifizierbare Bedeutung

Martin Düchs (Architectural Theory, St Pölten):
Vers une architecture morale – John Ruskin’s Seven Lamps of Architecture as the starting point for a wave of moralising in modern architecture (theory)

Karl Hepfer (Philosophy, Erfurt):
7: Don’t Take a Prime for the Answer!

Joachim Knape (Allgemeine Rhetorik, Tübingen):
Maß, Zahl und Gewicht. Paradigmen als Ordnungsmodelle der Welt

FRIDAY, 17 July 2026

9–13: Session 2

Nadia Koch (Klassische Rhetorik, Salzburg):
Vier plus drei: Der Farbkasten, aufgeräumt

Wiebke Leister (Royal College of Art, London):
Der siebte Sohn eines siebten Sohnes – ein Schlangenheiler

Riccardo Olivito (Classical Archaeology, Lucca):
Seven days a week. On a hebdomadal representation from Pompeii

Thomas Schirren (Griechische Philologie, Salzburg):
Die Sieben Weisen

14.30–19.30: Session 3

Julian Schreyer (Classical Archaeology, Erlangen):
Mithras

Thorsten Uthmeier, Andreas Pastoors (Prehistory, Erlangen)

Ute Verstegen (Christian Archaeology, Erlangen)

Eleonora Voltan (Classical Archaeology, Madrid):
Architecture of the Seven Planets: Spatial Syntax, Solar Orientation, and Ideology at the Severan Septizodium

Carina Weiß (Klassische Archäologie, Würzburg):
Plejaden-Magie. Das Siebengestirn in der antiken Glyptik und mittelalterlichen Esoterik

Andreas Grüner (Classical Archaeology, Erlangen):
Seven and Eight in the Pantheon, illustrating the profound problem of numerology in Greek and Roman Architecture

Concluding remarks

Conference venue: Wassersaal, Orangerie, Schlossgarten 1, 91054 Erlangen.

Organisation: Andreas Grüner, Elisa Bernard, Julian Schreyer.

The workshop is part of the series "Archäologische Grundbegriffe".