But when hospital staff showed the mysterious man a piano, he started playing -- and wouldn't stop for two hours.
The man was found wandering the streets in a coastal town in southeast England over a month ago and he has refused to communicate ever since, except through music.
"I cannot get within a yard of him without him becoming very anxious," said Michael Camp, the social worker assigned to the tall blond man dubbed the "Piano Man" by hospital staff. "Yet at the piano he comes alive."
Staff at Medway Maritime Hospital launched a search Monday for anyone who knows the man, who is in his 20s or early 30s and was found April 7 in the coastal town of Sheerness. He is being treated at a psychiatric unit in nearby Dartford.
"Someone, somewhere must be missing him," said Camp. "At the moment we only have six weeks' of history of this man to work on, which makes it very hard."
The British press has likened the case to the Oscar-winning 1996 movie Shine, about acclaimed pianist David Helfgott, who suffered a nervous breakdown. But there appears to be little question the man is any more than an accomplished amateur.
Hospital chaplain the Rev. Steve Spencer said the man "is not the virtuoso that he has been portrayed in the press. He knows a small number of tunes and plays them over and over _ I recognized some John Lennon and a snippet from Tchaikovsky's Swan Lake."
"When he plays, he is totally focused -- he cuts out everything else and it makes him calmer."
Hospital staff discovered the man's musical ability after they gave him paper and pencils and he produced a detailed sketch of a grand piano. They showed him to a piano
"When we took him to the chapel piano it really was amazing. He has not spoken since the day we picked him up. He does not make any sounds but I think I can communicate with him through tiny nods," Camp said.
Authorities have released a photograph of the man, who has cropped hair that may have been dyed blonde. They have also released his piano drawing. Relatives or anyone else who recognizes him are being urged to call a national missing persons help line.
"By the way he plays the piano, he is clearly educated and intelligent," said Camp. "If someone comes forward with information, then we can take this emotional case forward."
Camp said when the man was brought to the hospital "there was nothing obviously wrong with him, but because of his presentation the police felt he had a mental health problem."
"He came to us in a smart black suit and tie, which was soaked," he added. "He appears to be very anxious but we have no idea why. He has, as far as we know, committed no crime but we feel he is very vulnerable."
When the man was found, officials initially thought he might have come from a funeral, but inquiries showed he had not been to any services in the vicinity.
Then interpreters from Poland, Latvia and Lithuania were brought in to see if he was from Eastern Europe, and possibly an asylum seeker, but no one was able to get through to the man.
In addition, all the labels were removed from his clothing, making it even harder to identify him.
"There is no doubt that this man is extremely distressed and depressed," said Camp, the social worker. "He has started crying over the last week or so. It may be that some sort of trauma has made him like this."
