diff --git a/kwant/physics/symmetry.py b/kwant/physics/symmetry.py
index 9e53ab807c71a2f04af587846c2099685077d436..6c648a95d1687acd2b4c6318277e635ae6e6171a 100644
--- a/kwant/physics/symmetry.py
+++ b/kwant/physics/symmetry.py
@@ -37,7 +37,7 @@ _names = ['Time reversal', 'Particle-hole', 'Chiral']
 _signs = [1, -1, -1]
 
 class DiscreteSymmetry:
-    """A collection of discrete symmetries and conservation laws.
+    r"""A collection of discrete symmetries and conservation laws.
 
     Parameters
     ----------