Sorry novice, (no vice?) it's the percocets
The beard is the same even though the hair is replaced at a steady rate. The creek behind my house is thousands of years old even though the water is changing constantly.
The rivers to the sea thing is different. There are many rivers that empty into inland lakes that do not drain to the sea, ever. Yes they evaporate and precipitation ends up in the sea directly or via another river. Or the lake water percolates through the earth into an aquifer and then gets pumped to the surface to continue to the sea. But that's like saying a hair falls out of my beard, goes through the sewer system to the sludge, gets spread on a corn field, I eat the corn and grow a new hair. Pretty much a stretch.