diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 604bab0f0..03fa7c801 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -1259,7 +1259,7 @@ def process_deposit(state: BeaconState,
         withdrawal_credentials,
     )
 
-    if valid_proof:
+    if proof_is_valid:
         validator_pubkeys = [v.pubkey for v in state.validator_registry]
     
         if pubkey not in validator_pubkeys: