"Tell me what you eat, and I will tell you who you are."
That famous saying dates back to 1825, to French epicure Jean Anthelme Brillat-Savarin.
He meant that people define themselves by what they will -- or will not -- eat. And his words could not be a better description of why people are reacting so strongly to the horse-meat scandal in the European Union today.
The crisis began in Ireland in mid-January with the discovery of horse meat disguised as beef in some supermarkets.
Since then, up to 100 percent horse meat has been found in several ranges of prepared frozen food in Britain, France, and Sweden. There are fears food products in a dozen more EU countries could be affected, too.
Some consumers are furious because the meat they bought was mislabeled and they feel duped. But for others, something more powerful seems to be at work.
"There is a high degree of emotionalism because of the history of the horse," says Victor B. Meyer-Rochow, a professor of biology at Jacobs University in Bremen, Germany. "[It is] seen as such a stately, such a glorious, noble animal, especially if it is declared as some other kind of meat."
According to Meyer-Rochow, much of the outrage comes from people feeling they have been tricked into breaking a deeply felt cultural taboo or, more specifically, a food taboo.
Having studied the history of food taboos, he says every society has them and that often their origins are lost in the mists of time. They range from ancient tribal beliefs in the power of certain animal spirits that must not be offended, to religious dietary laws that proscribe eating certain foods or combinations of foods because they are deemed unhealthy or unclean.
But they also include more informal rules regarding which animals a society regards as man's natural companions and which are a food resource. Since horses have historically fallen into both those categories, their status is particularly complicated.
"Certainly, horse meat is eaten in many parts of Europe and in many parts of the world and there is no scientific reason why one should not consume horse meat," says Meyer-Rochow.
Today, however, the norm in most European countries is to give horses almost the status of family pets.
Horses have gained that status over the past century as cars, trucks, and tractors have freed them from being beasts of burden -- and afterward, food for the poor -- while leaving them with their more esteemed role as a sports and leisure partner.
In some countries -- particularly the United Kingdom and Ireland -- nobody eats horse meat, while in other countries, such as France and Switzerland, some do and some don't.
Meyer-Rochow says that when a taboo regarding what to eat or not eat is broken, the reaction can be furious because the taboos are not just about eating habits.
They are also a big part of how people in one area of the world see themselves as different from people in another.
"Any kind of food taboo unites people of a particular group and that makes them different from the others," says Meyer-Rochow. "So, by saying the horse is such a noble animal and we will not eat this meat, we elevate ourselves above those who treat the horse as if it were just a rabbit or something else."
That could be reason enough to suspect that, as the horse-meat scandal now spreads across Europe, the indignation will not only continue but continue to be taken very seriously.
Just one measure of how seriously was Romania's reaction
on February 11 as suspicions in France turned to it as the source of the disguised horse meat.
Romanian President Traian Basescu said his country's credibility could be damaged for "many years" if a Romanian meat supplier is found to be at fault for the scandal.
To judge by the outrage in Europe, it is no idle warning.