What is the measure your customers use to divide their day and yours? Is morning before lunch, and evening after dinner? Or do you work by clock and sun? Which word would you use to describe the dinner you served at 10am - the norm in King Henry VIII's day?
The timing and nature of our meals have never been fixed. They change over time, between social classes, and according to work and leisure patterns. Yet prevailing fashions have tremendous impact on our industry, affecting the sort of food cooked, the tilt of the menu, the hours worked, and the style of new restaurants and pubs.
Forty years ago, at the beginning of his career at Clifton House Hotel in Nairn on the north-east coast of Scotland, Gordon Macintyre expected every guest to eat breakfast, lunch, tea and dinner every day of their stay. This metronomic refuelling - the English stomach "does not care to remain inactive for more than four or five hours", wrote one historian - determined the size of each meal, or else the guests would not even have had the energy to crawl to the beach.
In 1995, Clifton House works to a different timetable. Breakfast runs at least an hour later, and may last until midday; lunch is barely noticed as a serious interruption; tea is rarely more than a pause for a cuppa; and dinner, which after World War II was served from 7pm to 7.30pm, is now largely confined to between 8pm and 9pm.
The current trend of grazing or snacking our way through the day means we are eating smaller meals less frequently and, when we do eat, it is usually later in the day.
Historically, the times and names of meals have differed from person to person and place to place. For example, when Victorian ladies were being served lunch, their servants would be eating dinner.
When a businessman in London was beginning to think about his dinner, his competitors in Leeds or Bradford might be scoffing high tea.
Today, if you asked people to name the meal they were eating, they might say it was supper, tea, or dinner; lunch or dinner; breakfast or brunch. In response to this vagueness, restaurants provide the all-day breakfast, and menus that don't change from midday to midnight.
The linchpin of the day has always been dinner - or the main meal, to use a value-free term. The only constant in this truly moveable feast is that, as the centuries have rolled by, dinner has got later and later.
When Shakespeare was writing, dinner was eaten at the end of the morning; by the time of the Georgian poet Alexander Pope, at the beginning of the 18th century, it was 3 o'clock in the afternoon, while some of the "faster set" choose to dine at 4pm.
During the Victorian era, dinner time moved towards evening: some preferring 5pm to 6pm; others, depending on the importance of the evening and whether there were guests, restrained their appetites until 7pmor 8pm.
Dinner more or less stuck at these times until the post-war years, when there was a further advance to 8.30pm or 9.30pm, particularly in London (almost, though not quite, Spanish hours).
The biggest change in our dining habits, then, has been the main meal's move from the middle to the end of the day. There was no such meal as lunch until the days of Jane Austen, at the beginning of the last century. Before this, dinner was positioned between breakfast and supper.
Today many social groups eat dinner at the end of the day. Supper has been suppressed. Lunch, the secondary meal, leads up to dinner.
Of all our eating habits, lunch appears to have changed the most during the last century. It began, like afternoon tea, as a women's meal - the ladies lunched, but only at home. It was a break in the middle of the day, a way of surmounting the expanding space between breakfast and dinner at the end of the afternoon.
Men, increasingly, needed the whole day to pursue business, and more of them were working away from the home.
The derivation of the words "lunch" and "luncheon" are different, though both relate to a simple snack, taken to get through the day. Lunch comes from the Spanish "lonje" or "slice". Luncheon is an English word for lump or gobbet of bread or cheese.
Both became common usage during the 17th century, though the idea of a real meal called lunch came later. The consequence of this derivation is that luncheon is not the formal version of "lunch". In fact, in Regency England, the word "lunch" was thought more pukka than "luncheon".
During this period, the husband would slave away at the counting-house while wifey nibbled lunch at home. During Victoria's reign the habit spread to both sexes. Dinner moved further towards night-time and everyone needed something between an 8am breakfast and dinner at 7pm.
Wartime: power lunching
For lunch, the probable high point came during World War II. Rationing meant food was in short supply on the domestic front, yet workers did not need food coupons to eat in works canteens and restaurants. It was in their interest to stoke up at lunchtime and thus ease the pressure on the diminishing larder at home. In consequence, lunch entered the big time for the restaurant business. As many meals were served then as at dinner. When lunch became a main meal - called midday dinner by some - the later meal at home started to be called "supper".
A meal consisting mainly of cold cuts and lighter dishes, supper was originally at the end of the evening, shortly before bedtime. It was a formal meal in as much as outsiders were invited to it. The practice is still reflected in the post-theatre suppers served in West End restaurants. The phrase pre-theatre supper, still in use, is more doubtful - perhaps it should be dinner!
Supper has come to mean a non-pretentious evening meal, with guests but without ceremony - though most people who eat it will often not have had a bigger meal in the course of the day.
It has taken some years for habits to change. Lunch exists, certainly, but far more nationally than it used to. Sandwiches, pub food, fast food, or just sweets and snacks - these are the preferred choices of people eating outside the home during working hours.
Even in restaurants lunch is lighter and more quickly eaten than dinner. In the past it would often have been of equal weight.
Although the true origin of the exact name of the meal being sent across the hotplate may seem of little importance to the chef who cooks it, perhaps it should. Understanding how the patterns of eating have changed and developed may give us the key to unlocking the mystery of the next shift in our eating habits - which will determine the working pattern of the next generation of chefs.
And each generation's restaurants has to move in step with its preferences. How many places would still be in business today if they served dinner from 6.30pm to 8pm and then closed their doors?