diff --git a/README.md b/README.md
index b810edb0..ba606dfe 100644
--- a/README.md
+++ b/README.md
@@ -17,11 +17,17 @@ Named after the [Ruddy Turnstone](https://en.wikipedia.org/wiki/Ruddy_turnstone)
 
 **What is a harness?**
 
+<p align="center">
+  <a href="https://raw.githubusercontent.com/turnstonelabs/turnstone/main/docs/diagrams/harness.png">
+    <img src="https://raw.githubusercontent.com/turnstonelabs/turnstone/main/docs/diagrams/harness.png" alt="ℋ : s_{n+1} ~ T(s_n) for n < τ_H — the whole controlled loop: π lowers state to context, M_W proposes a readout, γ authorizes it, Q_E acts on the world, ρ verifies and folds back" width="960"/>
+  </a>
+</p>
+
 ```
-ℋ :  s_{n+1} ~ T(s_n)   for n < τ*,    T = ρ ∘ (M_W ∘ π, E)
+ℋ :  s_{n+1} ~ T(s_n)   for n < τ_H
 ```
 
-[**the primer →**](PRIMER.md)
+[**the primer →**](PRIMER.md) · [**the formalism →**](HYPOTHESIS.md)
 
 ### Release Tracks
 
diff --git a/docs/diagrams/harness.png b/docs/diagrams/harness.png
new file mode 100644
index 00000000..5093806b
--- /dev/null
+++ b/docs/diagrams/harness.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:6e2bfdf968e96f3720ed58674103288e2f57e9c056f5c479a57f37a849f3e69c
+size 821878