The grandfather told his grandchild that, due to his wife passing, he had started cooking. The grandchild didn't expect his grandfather to ever begin cooking, so they headed towards the dining room to see what he made for dinner.
When they sat down, the grandchild noticed that the food looked delicious, and tasted delicious too.
But one think bothered him. He noticed that the plates were a little grimy and the silverware looked dirty. So, he asked his grandfather "Do you wash your dishes well?". The grandfather simply replied "They're as clean as cold water will get them".
The next week he made another trip to his grandfather's house.
Again, the grandfather cooks a beautiful dinner that tastes delicious. But, the grime on the plates and silverware still bothers the grandchild. He said "Grandfather, I don't think these dishes are clean. Are you sure you wash them well?" The grandfather replied "They're as clean as cold water will get them!"
The next week they meet again at the grandfather house. This time, upon noticing the dirty dishes, the grandchild says "Grandfather, I'm going to help you wash the dishes after dinner". The grandfather only says "Okay, but they're as clean as cold water will get them".
After dinner they carried the dishes into the kitchen. The grandfather began to set the dishes on the floor. The grandchild, confused, decided to see what he was up to.
After the dishes were arranged on the floor, the grandfather says "Come here, cold water" as his dog runs in.