Well, there are several indicators of being a true "master diver", that transcend mere certifications.
1 - If you have an autographed picture of Jacques Cousteau in your bedroom, you might be a master diver.
2 - If you buy all the used gear you see on Craigslist, you might be a master diver.
3 - If you have seen all episodes of Sea Hunt, and get oddly aroused, you might be a master diver.
4 - If your vehicle has more than 3 DIR, GUE, or Halcyon sticker, you might be a master diver.
5 - If your email password is "PADI-DADDY" you might be a master diver.
6 - If you have a lot more regulators than tanks, you might be a master diver.
7 - If you have wind chimes made of old aluminum tanks, you may be a master diver.
8 - If you have more than 2 Shearwater computers, you might be a master diver.
9 - If your wife is driving a 20 year old clapped out Corolla, but you have a new Liberty rebreather and Suex scooter, you are an arsehole, but may be a master diver.
These are just a few examples.