diff --git a/src/math/Matrix4.js b/src/math/Matrix4.js
index b8aaea42c7cf4ad82e3f41c767e2f99fc4a9c174..3faa8c69fa4531dc8db1ec90caa4dce006724e7c 100644
--- a/src/math/Matrix4.js
+++ b/src/math/Matrix4.js
@@ -250,8 +250,6 @@ THREE.Matrix4.prototype = {
 
 	multiply: function ( m ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		return this.multiplyMatrices( this, m );
 
 	},
diff --git a/src/math/Quaternion.js b/src/math/Quaternion.js
index 29a5a46ea7615617b17141ede8b1758ef48384a7..69bc3e1fffd17307938364b77c7799b20f23d583 100644
--- a/src/math/Quaternion.js
+++ b/src/math/Quaternion.js
@@ -233,9 +233,8 @@ THREE.Quaternion.prototype = {
 
 	multiply: function ( b ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		// from http://www.euclideanspace.com/maths/algebra/realNormedAlgebra/quaternions/code/index.htm
+
 		var qax = this.x, qay = this.y, qaz = this.z, qaw = this.w,
 		qbx = b.x, qby = b.y, qbz = b.z, qbw = b.w;
 
diff --git a/src/math/Vector2.js b/src/math/Vector2.js
index e744e58caaeff3d2f9c9e2ccf39a8b52f85de9df..f2c1f41761ab3cb186341b55740fd8ee2a44d9b4 100644
--- a/src/math/Vector2.js
+++ b/src/math/Vector2.js
@@ -77,8 +77,6 @@ THREE.Vector2.prototype = {
 
 	add: function ( v ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		this.x += v.x;
 		this.y += v.y;
 
diff --git a/src/math/Vector3.js b/src/math/Vector3.js
index 3de68944f6d8f7860b5eb33c598fc1a8631118e5..dc1b07bd4e9a2fa71edace168b3951d14e73dd85 100644
--- a/src/math/Vector3.js
+++ b/src/math/Vector3.js
@@ -92,8 +92,6 @@ THREE.Vector3.prototype = {
 
 	add: function ( v ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		this.x += v.x;
 		this.y += v.y;
 		this.z += v.z;
@@ -124,8 +122,6 @@ THREE.Vector3.prototype = {
 
 	sub: function ( v ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		this.x -= v.x;
 		this.y -= v.y;
 		this.z -= v.z;
@@ -146,8 +142,6 @@ THREE.Vector3.prototype = {
 
 	multiply: function ( v ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		this.x *= v.x;
 		this.y *= v.y;
 		this.z *= v.z;
@@ -414,8 +408,6 @@ THREE.Vector3.prototype = {
 
 	cross: function ( v ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		var x = this.x, y = this.y, z = this.z;
 
 		this.x = y * v.z - z * v.y;
diff --git a/src/math/Vector4.js b/src/math/Vector4.js
index 7b5afc72495e273adeb08764c9b077bce0436d96..c9e0eafae3328f97845bf1ee22825db078cf994c 100644
--- a/src/math/Vector4.js
+++ b/src/math/Vector4.js
@@ -103,8 +103,6 @@ THREE.Vector4.prototype = {
 
 	add: function ( v ) {
 
-		if ( arguments.length > 1 ) debugger;
-
 		this.x += v.x;
 		this.y += v.y;
 		this.z += v.z;