diff --git a/diffuse_implicit.py b/diffuse_implicit.py
index e4c6e39..4456de6 100644
--- a/diffuse_implicit.py
+++ b/diffuse_implicit.py
@@ -92,7 +92,7 @@ def diffuse(dt: ti.f32):
     solver.factorize(ImcD)
 
     # linear solve: solve
-    t_np1.from_numpy(solver.solve(t_n)) # t_np1 = t_n + c*D*t_np1
+    t_np1.from_numpy(solver.solve(t_n)) # (I - c*D) t_np1 = t_n
 
 
 def update_source_and_commit():
@@ -163,4 +163,4 @@ def temperature_to_color(t: ti.template(), color: ti.template(), tmin: ti.f32, t
         my_gui.show(f"images\output_{i:05}.png")
         i += 1
     else:
-        my_gui.show()
\ No newline at end of file
+        my_gui.show()