diff --git a/cobaya/prior.py b/cobaya/prior.py
index 0a066082b..a6bf9098f 100644
--- a/cobaya/prior.py
+++ b/cobaya/prior.py
@@ -282,7 +282,7 @@
           prior: [...]
           drop: True
         x:
-          value: "lambda logx: np.exp(x)"
+          value: "lambda logx: np.exp(logx)"
 
    Now, if you want to fix the value of ``logx`` without changing the structure of the
    input, do
@@ -294,7 +294,7 @@
           value: [fixed_value]
           drop: True
         x:
-          value: "lambda logx: np.exp(x)"
+          value: "lambda logx: np.exp(logx)"
 
 
 .. _prior_inheritance: