In a rather acid moment, my publisher once said that all my books could secretly be titled ‘Fun Stuff I Have Found Out’. He did not mean it unkindly, or at least I tell myself he didn’t. And up to a point it’s a fair cop, guv. I came to history-writing by the back door. I was writing a biography of four Victorian women, and to understand their own particular lives I felt I needed to know more about the lives most women of their background and time lived. My next four books, to a greater or lesser, extent focused on exactly that: how did the people of the time live; what did they do, what did they see, feel, smell; how did they amuse themselves, what was available to them on a day-to-day basis? If we don’t know about ordinary life, goes my brain, how can we understand what motivates the less ordinary?

The historian Robin Winks divided history into ‘three things: what happened in the past, what people believe happened in the past, and what historians say happened in the past’. This tripartite division is a good description of what history is. History-writing, however, can just as well divide into two schools: theory, and ‘stuff’. Stuff falls into Winks’ ‘what happened in the past’ category, while theory spills across the other two. But stuff encompasses more than just ‘what happened’. It is also ‘what was it like when it happened’.

Take urbanization, for example. Theory discusses the broad sweep of city growth and the socialization of populations. Stuff uncovers that, in the new cities, when traffic began to be segregated according to different types of transport, carts went in one lane, pedestrians and horses in another: the division was wheels vs. legs. Not an insight that alone will set the world on fire but one that, nonetheless, does indicate a mindset revealingly different to our own.

The source-materials for stuff are also pleasantly far-ranging. I would never take Tennyson’s description of ‘streaming London’s central roar’ as evidence of ‘what happened in the past’. It might mean the city was noisy, or it might be a flight of fantasy. Nor Dostoevsky calling London a city filled with ‘the screeching and howling of machines’ – he is hardly known as being the most even-keeled of writers. But then there is Dickens. Novel after novel abounds with throw-away lines like this from Our Mutual Friend, where one character asks another, ‘Would you object to turn aside into this place…[to one] where we can hear one another better than in the roaring street?’ Add in visitors’ reports of being unable to hear a sermon in St Clement Danes on a Sunday over the sound of the traffic in the Strand, or Jane Carlyle complaint of the ‘everlasting sound in my ears, of men, women, children, omnibuses, carriages, glass coaches, street coaches, waggons, carts, dog-carts, steeple bells, door bells, gentlemen-raps, twopenny post-raps, footmen-showers-of-raps, of the whole devil to pay…’ from her small by-street in Chelsea, and Tennyson and Dostoyevsky now appear to be merely reporting.

I do understand the qualms of the theory-ers, who question whether the experiences of individuals alone can be the basis on which to formulate more abstract ideas about society. Yet stuff allows us a mosaic-style formation of a picture. One tile tells us little: it is too highly coloured, or too pale; but combine the many, many tiles that make up stuff, and a vivid picture emerges. We can stop with these pictures – that may be all we ask of ‘what happened in the past’. But my view is that, carefully assessed and weighed, stuff can indeed lead more naturally to theory, to understanding how the people of the past thought about what happened.

It took me a phenomenally long time to discover exactly how a doorstep was whitened in the nineteenth century. Every household-management book assured its readers it had to be done daily, but detailed instructions were scanty, for the simple reason that it was done daily, and so everyone knew how. I was finally enlightened not by a book, but by my great-aunt (born 1905). The step was scrubbed down with boiling water. After it dried, a white paste was applied. (Details to be found in The Victorian House, should any of you kids decide to try this at home.) It was done first thing in the morning, she said, before they went to school, so she and her sister had to jump from the threshold to the path, because walking on the step would mark the white. How, I asked, wondering, did they get back in again after school? This was the revelation: ‘You could walk on it after eleven; everyone had seen it.’

This stuff therefore has two parts. First, the step was scrubbed before it was whitened; the whitening was not part of the cleaning process. And secondly, it was the very ephemerality of the white that was crucial. Whitening a doorstep was not about cleanliness, it was about respectability. The transient nature of the white indicated to others that you had it: you had cleaned that day, and would clean again the next. So here, stuff leads to theory. What happened, what people thought about it, and why.

For the book I am currently working on, an attempt to outline the development of the idea of home, I am by the nature of the subject dealing more with theory than I ever have before. For the first year, I felt like a cow in ice-skates: please let me have my stuff back, I cried. I can trace the development of artificial lighting with no trouble. I can do it with both arms tied behind my back. Please please please don’t make me write about why, as lighting became brighter, cheaper and more accessible, window-curtains moved from being rarities to being routine, or why the trends in decoration pronounced darkened rooms more aesthetically pleasing. (Although my stuff-nature leapt upon the nomenclature. In Germany in the late nineteenth century, one especially gloomy tendency was known as the braune Soße – gravy – style of interior decoration.)

Sometimes I think theory is like dealing with a particularly inquisitive five-year-old. Why was there an Industrial Revolution? Because of the consumer revolution. OK, so why was there a consumer revolution? Because of the… and we’re off, an endless series of ‘whys’ pushing each question further and further back.

At other times, I am amazed not so much by the material (although that is astonishing too), as by Winks’ second category: ‘what people think happened’. Or, in some cases, what they refuse to believe happened; we refuse to move from stuff to theory. Dutch academics have produced exceptional work on sixteenth-century inventories, comparing the paintings of the Golden Age to the actual design and contents of the houses supposedly depicted. There is, they show, little overlap – barely any houses had marble floors, brass chandeliers, carpets on tables or even owned musical instruments; meanwhile many items that were in common use, such as strip-matting on the floors, were rarely or barely ever painted. The Dutch of the sixteenth century knew these pictures did not depict reality; it is we, in the intervening centuries, who have lost sight of that.

But the fascinating thing is how little purchase this work has had, how rarely it has been incorporated into the mainstream of general knowledge, despite – or indeed because – of the popularity of the paintings. The reason for this obscurity, of course, moves us from stuff (the inventories) to theory. The curator and design-historian Peter Thornton knew of this work, but continued to argue for verisimilitude of Dutch golden age art: the departure from reality for artists ‘is never all that large’, he wrote. And how, he challenged, if there were no carpets in houses, could artists ‘find carpets on floors to depict so accurately’, taking for granted that artists paint only the world about them, that they do not own props, nor create staged settings to paint.

In part, Thornton’s rejection of the research may have been one of age. He had relied heavily on paintings and engravings for his great histories of interior decoration; to accept the heavily symbolic nature of supposedly realist works  which emerged as he reached his eighties would bring into question a lifetime’s work. But his refusal mirrors the seemingly inexplicable obscurity of such fascinating material.

His refusal is ours. We really don’t want to know that these paintings are not realistic. From their re-popularization in the nineteenth century, these paintings have been a major component in what we think of when we think of the word ‘home’. We want those tranquil, golden-lit rooms to have been real, to be, now, a place that once existed, and might therefore exist again. If we accept they are imaginary, we must accept that our own notions of home are, in part, imaginary too.

Is this theory correct? I don’t know. But what I do know is this: stuff doesn’t lie.

First published in The Author