Why isn't SceneManager.SetActiveScene allowing me to set the scene with it's index number?

Today I started working on a script for dynamic loading and instantly hit a wall with SceneManager. Having little to no experience with loading scenes in unity, I’ve read up on what I could with the Scripting API and manual but can’t figure out why I can’t set a scene as active at all.

using UnityEngine;
using UnityEngine.SceneManagement;
using System.Collections;

public class worldLoader : MonoBehaviour
{

    // 
    void Start () {

        Scene CurrentScene = SceneManager.GetActiveScene();
        Debug.Log(CurrentScene.name);
        Debug.Log(CurrentScene.buildIndex);


        if (CurrentScene.name != "MasterScene")   
        {
            SceneManager.SetActiveScene(0);
        }


    }

}

During initialization, the script checks the name of the current scene and compares it to the name I gave it, and in the if statement I run into the problem where SceneManager.SetActiveScene won’t recognize 0 as the build index of a scene and I’m not sure what the problem is after searching for other examples.

SceneManager.LoadLeve(0);

if (CurrentScene.name != “MasterScene”)
{
SceneManager.SetActiveScene(SceneManager.GetSceneByName(“MasterScene”));
}

I ended up with this after searching with different terms.