what does the ghost of christmas past show scrooge

The ghost of Christmas past shows Scrooge his past, and the way he used to be before he became the grumpy, selfish old man he is now. It takes him through various moments in his life, including his time as a young boy, when he was full of joy and optimism. It also shows him the people he has lost along the way, and how he has become so isolated and alone.