The Tang Dynasty was in a transitional period of meal system. Some people had two meals, and some had three meals.

During the pre-Qin period, the ancients generally followed the eating habit of "two meals a day", that is, the "two-meal system", which was also used to adapt to the time needs of farming.

In the relevant records of oracle bone inscriptions, there are related records of "big food" and "small food".

According to the timing method of the Shang Dynasty, 7 to 9 a.m. is called "big food" and 15 to 17 p.m. is called "small food". The time for eating two meals has become a convention, so it is adopted as the proper name of the hour.

However, even though society generally adopted the "two-meal system" during this period, a certain number of families among the wealthy middle and upper classes still adopted the three-meal-a-day system.

Since the Han Dynasty, the eating habit of three meals a day has been initially developed. At this time, the three meals also had relatively fixed and proper names.

We now call the three meals breakfast, lunch and dinner, but at that time they were not called "three meals", but "three meals".

This was also the case in the Sui and Tang dynasties.

Of course, the meal system in the entire society is not uniform. For example, the emperor's diet is different from that of ordinary people. They generally eat four meals a day, while some poor families continue to practice the two-meal system.

Extended information: Human beings once experienced an era of raw food, that is, most of the food eaten by humans was raw and cold food, which is what we generally call "ruining hair and drinking blood".

In most cases, humans eat food directly as long as they find it. In some cases, they even cannot find food to satisfy their hunger.

At this time, food types were relatively scarce, and food sources were also highly unstable. Sometimes they were abundant, sometimes they were in short supply. The so-called meal system had not yet been formed, and naturally there was no fixed eating time.

In this case, the meal preparation is basically irregular.

When humans started agricultural society, growing grains became the main way for people to obtain food.

Because the planting time of grains is relatively certain, daily routines that are consistent with this gradually emerged, and meal preparations also began to appear and gradually develop.

In the long historical development process, whether people adopt the "two meals a day" system or the "three meals a day" system, it is actually based on certain social and historical conditions at that time.