How far back can you remember? What are your first memories, and how detailed are those earliest recollections? Perhaps you could describe a handful of incidents from your first three years. But would your words amount to more than snapshots of the past? It’s unlikely, unless you are Tito.

And what about your earliest thoughts and feelings? Could you say what was going through your mind at the age of two-and-a-half, or explain your reactions then on hearing a particular piece of news? Tito can. But then Tito is an extraordinary child.

For one thing, he doesn’t speak. So when, at the age of eight, he told the world about his life so far, he did so by writing with a pencil - sometimes, even, by pointing to letters on an alphabet board.

But an inability to speak is only one of the things that sets Rajarshi Mukhopadhyay, known as Tito, apart from his peers. For this little boy from south India suffers from a parcel of mental disabilities that has afflicted a proportion of children at every time and in every culture.

For the lack of a better term, this condition is called autism. And if you want a fresh insight into what autism means, you should listen to Tito. It’s not that he understands exactly. Nobody does. But he can tell you what autism feels like for him. And, most intriguingly of all, he can tell you what it felt like almost from the beginning. For Tito has an astonishing ability to recall his earliest experiences, and to set down in writing thoughts that are far in advance of his years.

“Nights were terrible. He searched everywhere for his shadow. He flapped to call it, there was nothing but darkness. He cried for it, betrayed by the friend.” That’s Tito talking, describing on the first pages of this astonishing book of autobiography and poetry just what it felt like to be a young infant - how he flapped his hands in agitation (as many autistic children do) and was distressed by the loss of his shadow. And yes, he is referring to himself in the third person. Already the boy writes like a psalmist.

From the outset, Tito says, he was hampered by an inability to perceive his body as a single entity. When he flapped his hands, or whirled in imitation of an electric ceiling fan (spinning is another autistic trait), his arms and legs seemed momentarily to come together. But his senses would not work in unison. He couldn’t hear what he aw or see what he heard. And so he could not - cannot - speak.

Tito remembers when he first made the connection between the movements of his mother’s mouth and the songs she sang. “That looked easy,” he writes.” For a few days after that, he was in front of a mirror finding out a way to move his lips - pleading them to move in a silent way. But they did not flutter or move like mother’s. All his image did was stare back. That was a terrible jolt.

“Another frustration and a great fear grew. He refused everything that belonged to ‘the world’. He waited for some remarkable thing to happen and started to meditate for an answer.”

As a toddler, Tito says, he learned to masturbate “on the edge of the bed or a sofa” as a way of escaping his uneasiness about his inability to communicate. He recalls not only his own actions, but also his mother’s reaction. And he has, it seems, a shrewd understanding of the situation.

“She hardly realised what her two-and-a-half-year-old son was up to,” Tito writes. “It took her about a couple of weeks to find out and get worried. I can still remember her efforts to divert his attention by giving him books to see.”

If you find Tito’s account of his early life hard to accept, you are not alone. “We were intrigued, but inclined to be sceptical,” writes Lorna Wing in the foreword. Dr Wing, a consultant psychiatrist and expert on autism, had been invited to meet Tito and his mother on a flying visit to the National Autistic Society in December 1999.

“There was no doubt that some individuals with autism have one or more remarkable talents far ahead of the rest of their abilities,” she writes. “However, these talents usually involve visuo-spatial or rote memory skills such as calendar calculations, numbers, drawing, remembering train timetables, and so on.”

But here was a boy so disabled as to be, in all practical ways, totally dependent on others (“at one point he grabbed my hand to use it as a mechanical tool to turn a stiff door handle”, Dr Wing writes), yet who could not only write complex sentences but use them to express philosophical thoughts.

After a day observing and testing Tito, Dr Wing and the assembled experts were satisfied that the ideas he expresses are indeed his own. His book, she says, “is essential reading for anyone wanting to understand the nature of autism”.

Tito himself writes: “Men and women are puzzled by everything I do. My parents and those who love me are embarrassed and worried. Doctors use different terminologies to describe me. I just wonder.”