"You are old, Father William," the young man said, noting the father's aged appearance and white hair. He questions whether Father William's habit of standing on his head is appropriate for someone of his age. The young man's remark suggests concern about the potential risks of such unusual behavior for an elderly person.

"In my youth," Father William responded, reflecting on his past, "I feared it might injure the brain." This reply implies that as he aged, his perspective on the activity changed, and he no longer sees it as dangerous, highlighting a contrast between youth and old age and the different attitudes towards risky behaviors over a lifetime.