There are two methods for investigating consciousness; One subjective, the other objective. The first is philosophical, the second is a physical. And they should lead to the same answer.

Both sides will claim their method to be the right one. And from time to time one will seem better than the other. But ultimately, some questions will be left unanswered. And both methods will break down. And you will want to fill in the gaps.

But you'll realize that one may complement the other. And you may decide the course ... but you'll never be sure.