Why in Boolean type there are two fields with the same value?

internal const int True = 1;
internal const int False = 0;
internal const string TrueLiteral = "True";
internal const string FalseLiteral = "False";

and

public static readonly string TrueString;
public static readonly string FalseString;

static Boolean()
{
    TrueString = "True";
    FalseString = "False";
}

in reflector generated code, methods don't use those strings but:

public string ToString(IFormatProvider provider)
{
    if (!this)
    {
        return "False";
    }
    return "True";
}

would't it be better to use those const values?