diff --git a/src/nix/why-depends.cc b/src/nix/why-depends.cc
index c39a0435d..55bb43f95 100644
--- a/src/nix/why-depends.cc
+++ b/src/nix/why-depends.cc
@@ -82,7 +82,9 @@ struct CmdWhyDepends : SourceExprCommand
         store->computeFSClosure({packagePath}, closure, false, false);
 
         if (!closure.count(dependencyPath)) {
-            printError("'%s' does not depend on '%s'", package->what(), dependency->what());
+            printError("'%s' does not depend on '%s'",
+                store->printStorePath(packagePath),
+                store->printStorePath(dependencyPath));
             return;
         }