CZ gave a gold bar to Peter Schiff with a serial number, then asked Peter whether this gold bar is real gold or not?
Peter picked up the gold bar and said he couldn't tell. He only knew that his bracelet was real gold, while this gold bar was not.
CZ wanted to use this situation to show a superior point of Bitcoin compared to gold, which is that Bitcoin cannot be counterfeited on the blockchain while physical gold always carries the risk of authenticity.
