diff --git a/src/Validator/Messages.php b/src/Validator/Messages.php
deleted file mode 100644
index 54a5ba6..0000000
--- a/src/Validator/Messages.php
+++ /dev/null
@@ -1,139 +0,0 @@
-<?php
-namespace GraphQL\Validator;
-
-use GraphQL\Utils;
-
-class Messages
-{
-    static function missingArgMessage($fieldName, $argName, $typeName)
-    {
-        return "Field $fieldName argument $argName of type $typeName, is required but not provided.";
-    }
-
-    static function badValueMessage($argName, $typeName, $value)
-    {
-        return "Argument $argName expected type $typeName but got: $value.";
-    }
-
-    static function fragmentOnNonCompositeErrorMessage($fragName, $typeName)
-    {
-        return "Fragment $fragName cannot condition on non composite type \"$typeName\".";
-    }
-
-    static function inlineFragmentOnNonCompositeErrorMessage($typeName)
-    {
-        return "Fragment cannot condition on non composite type \"$typeName\".";
-    }
-
-    static function unknownArgMessage($argName, $fieldName, $typeName)
-    {
-        return "Unknown argument $argName on field $fieldName of type $typeName.";
-    }
-
-    static function unknownTypeMessage($typeName)
-    {
-        return "Unknown type $typeName.";
-    }
-
-    static function undefinedVarMessage($varName)
-    {
-        return "Variable \$$varName is not defined.";
-    }
-
-    static function undefinedVarByOpMessage($varName, $opName)
-    {
-        return "Variable \$$varName is not defined by operation $opName.";
-    }
-
-    static function unusedFragMessage($fragName)
-    {
-        return "Fragment $fragName is not used.";
-    }
-
-    static function unusedVariableMessage($varName)
-    {
-        return "Variable \$$varName is not used.";
-    }
-
-    static function typeIncompatibleSpreadMessage($fragName, $parentType, $fragType)
-    {
-        return "Fragment \"$fragName\" cannot be spread here as objects of " .
-        "type \"$parentType\" can never be of type \"$fragType\".";
-    }
-
-    static function typeIncompatibleAnonSpreadMessage($parentType, $fragType)
-    {
-        return "Fragment cannot be spread here as objects of " .
-        "type \"$parentType\" can never be of type \"$fragType\".";
-    }
-
-    static function noSubselectionAllowedMessage($field, $type)
-    {
-        return "Field \"$field\" of type $type must not have a sub selection.";
-    }
-
-    static function requiredSubselectionMessage($field, $type)
-    {
-        return "Field \"$field\" of type $type must have a sub selection.";
-    }
-
-    static function nonInputTypeOnVarMessage($variableName, $typeName)
-    {
-        return "Variable $${variableName} cannot be non input type $typeName.";
-    }
-
-    static function cycleErrorMessage($fragmentName, $spreadNames)
-    {
-        return "Cannot spread fragment $fragmentName within itself" .
-        (!empty($spreadNames) ? (" via " . implode(', ', $spreadNames)) : '') . '.';
-    }
-
-    static function unknownDirectiveMessage($directiveName)
-    {
-        return "Unknown directive $directiveName.";
-    }
-
-    static function misplacedDirectiveMessage($directiveName, $placement)
-    {
-        return "Directive $directiveName may not be used on $placement.";
-    }
-
-    static function missingDirectiveValueMessage($directiveName, $typeName)
-    {
-        return "Directive $directiveName expects a value of type $typeName.";
-    }
-
-    static function noDirectiveValueMessage($directiveName)
-    {
-        return "Directive $directiveName expects no value.";
-    }
-
-    static function badDirectiveValueMessage($directiveName, $typeName, $value)
-    {
-        return "Directive $directiveName expected type $typeName but " .
-        "got: $value.";
-    }
-
-    static function fieldsConflictMessage($responseName, $reason)
-    {
-        $reasonMessage = self::reasonMessage($reason);
-        return "Fields $responseName conflict because {$reasonMessage}.";
-    }
-
-    /**
-     * @param array|string $reason
-     * @return array
-     */
-    private static function reasonMessage($reason)
-    {
-        if (is_array($reason)) {
-            $tmp = array_map(function($tmp) {
-                list($responseName, $subReason) = $tmp;
-                $reasonMessage = self::reasonMessage($subReason);
-                return "subfields $responseName conflict because $reasonMessage";
-            }, $reason);
-            return implode(' and ', $tmp);
-        }
-        return $reason;
-    }
-}
diff --git a/src/Validator/Rules/ArgumentsOfCorrectType.php b/src/Validator/Rules/ArgumentsOfCorrectType.php
index 870eaf6..3ee3162 100644
--- a/src/Validator/Rules/ArgumentsOfCorrectType.php
+++ b/src/Validator/Rules/ArgumentsOfCorrectType.php
@@ -1,18 +1,12 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\ArgumentNode;
-use GraphQL\Language\AST\FieldNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\Printer;
 use GraphQL\Language\Visitor;
-use GraphQL\Type\Definition\NonNull;
-use GraphQL\Utils;
 use GraphQL\Validator\DocumentValidator;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class ArgumentsOfCorrectType
diff --git a/src/Validator/Rules/FieldsOnCorrectType.php b/src/Validator/Rules/FieldsOnCorrectType.php
index 3720040..524b303 100644
--- a/src/Validator/Rules/FieldsOnCorrectType.php
+++ b/src/Validator/Rules/FieldsOnCorrectType.php
@@ -1,15 +1,12 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\FieldNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Schema;
 use GraphQL\Type\Definition\AbstractType;
 use GraphQL\Utils;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class FieldsOnCorrectType
diff --git a/src/Validator/Rules/FragmentsOnCompositeTypes.php b/src/Validator/Rules/FragmentsOnCompositeTypes.php
index 6eeffa8..a57aaf5 100644
--- a/src/Validator/Rules/FragmentsOnCompositeTypes.php
+++ b/src/Validator/Rules/FragmentsOnCompositeTypes.php
@@ -1,16 +1,12 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\FragmentDefinitionNode;
 use GraphQL\Language\AST\InlineFragmentNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\Printer;
-use GraphQL\Type\Definition\CompositeType;
 use GraphQL\Type\Definition\Type;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class FragmentsOnCompositeTypes
diff --git a/src/Validator/Rules/KnownArgumentNames.php b/src/Validator/Rules/KnownArgumentNames.php
index f11673f..a5694e9 100644
--- a/src/Validator/Rules/KnownArgumentNames.php
+++ b/src/Validator/Rules/KnownArgumentNames.php
@@ -1,13 +1,10 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\ArgumentNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Utils;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class KnownArgumentNames
diff --git a/src/Validator/Rules/NoUndefinedVariables.php b/src/Validator/Rules/NoUndefinedVariables.php
index 98a0c38..c9486d9 100644
--- a/src/Validator/Rules/NoUndefinedVariables.php
+++ b/src/Validator/Rules/NoUndefinedVariables.php
@@ -1,17 +1,10 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
-use GraphQL\Language\AST\FragmentDefinitionNode;
-use GraphQL\Language\AST\FragmentSpreadNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\OperationDefinitionNode;
-use GraphQL\Language\AST\VariableNode;
 use GraphQL\Language\AST\VariableDefinitionNode;
-use GraphQL\Language\Visitor;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 /**
diff --git a/src/Validator/Rules/NoUnusedFragments.php b/src/Validator/Rules/NoUnusedFragments.php
index 9c3c74d..53d7b6b 100644
--- a/src/Validator/Rules/NoUnusedFragments.php
+++ b/src/Validator/Rules/NoUnusedFragments.php
@@ -1,14 +1,10 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\FragmentDefinitionNode;
-use GraphQL\Language\AST\FragmentSpreadNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\Visitor;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class NoUnusedFragments
diff --git a/src/Validator/Rules/NoUnusedVariables.php b/src/Validator/Rules/NoUnusedVariables.php
index ec1bc9b..cd939a2 100644
--- a/src/Validator/Rules/NoUnusedVariables.php
+++ b/src/Validator/Rules/NoUnusedVariables.php
@@ -1,13 +1,9 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\OperationDefinitionNode;
-use GraphQL\Language\Visitor;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class NoUnusedVariables
diff --git a/src/Validator/Rules/ScalarLeafs.php b/src/Validator/Rules/ScalarLeafs.php
index 9daf8ab..6da1723 100644
--- a/src/Validator/Rules/ScalarLeafs.php
+++ b/src/Validator/Rules/ScalarLeafs.php
@@ -1,13 +1,10 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
 use GraphQL\Language\AST\FieldNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Type\Definition\Type;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class ScalarLeafs
diff --git a/src/Validator/Rules/VariablesInAllowedPosition.php b/src/Validator/Rules/VariablesInAllowedPosition.php
index 2fe0724..86c0e2a 100644
--- a/src/Validator/Rules/VariablesInAllowedPosition.php
+++ b/src/Validator/Rules/VariablesInAllowedPosition.php
@@ -1,19 +1,13 @@
 <?php
 namespace GraphQL\Validator\Rules;
 
-
 use GraphQL\Error\Error;
-use GraphQL\Language\AST\FragmentSpreadNode;
-use GraphQL\Language\AST\Node;
 use GraphQL\Language\AST\NodeKind;
 use GraphQL\Language\AST\OperationDefinitionNode;
-use GraphQL\Language\AST\VariableNode;
 use GraphQL\Language\AST\VariableDefinitionNode;
-use GraphQL\Language\Visitor;
 use GraphQL\Type\Definition\ListOfType;
 use GraphQL\Type\Definition\NonNull;
 use GraphQL\Utils\TypeInfo;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\ValidationContext;
 
 class VariablesInAllowedPosition
diff --git a/tests/Validator/DefaultValuesOfCorrectTypeTest.php b/tests/Validator/DefaultValuesOfCorrectTypeTest.php
index 3dbbe59..a0ac412 100644
--- a/tests/Validator/DefaultValuesOfCorrectTypeTest.php
+++ b/tests/Validator/DefaultValuesOfCorrectTypeTest.php
@@ -3,7 +3,6 @@ namespace GraphQL\Tests\Validator;
 
 use GraphQL\Error\FormattedError;
 use GraphQL\Language\SourceLocation;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\Rules\DefaultValuesOfCorrectType;
 
 class DefaultValuesOfCorrectTypeTest extends TestCase
diff --git a/tests/Validator/FieldsOnCorrectTypeTest.php b/tests/Validator/FieldsOnCorrectTypeTest.php
index 45b498f..1c99dce 100644
--- a/tests/Validator/FieldsOnCorrectTypeTest.php
+++ b/tests/Validator/FieldsOnCorrectTypeTest.php
@@ -3,7 +3,6 @@ namespace GraphQL\Tests\Validator;
 
 use GraphQL\Error\FormattedError;
 use GraphQL\Language\SourceLocation;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\Rules\FieldsOnCorrectType;
 
 class FieldsOnCorrectTypeTest extends TestCase
diff --git a/tests/Validator/VariablesInAllowedPositionTest.php b/tests/Validator/VariablesInAllowedPositionTest.php
index 9dfe20c..d815f8a 100644
--- a/tests/Validator/VariablesInAllowedPositionTest.php
+++ b/tests/Validator/VariablesInAllowedPositionTest.php
@@ -3,7 +3,6 @@ namespace GraphQL\Tests\Validator;
 
 use GraphQL\Error\FormattedError;
 use GraphQL\Language\SourceLocation;
-use GraphQL\Validator\Messages;
 use GraphQL\Validator\Rules\VariablesInAllowedPosition;
 
 class VariablesInAllowedPositionTest extends TestCase