A once-commonplace aspect of Chinese life, which has largely – but not entirely – disappeared, is the use of hand signals. They evolved with the popularisation of Buddhism and spread from India into China more than 2,000 years ago, eventually transforming in form and purpose.

Mendicant monks in China, as in other parts of Asia, could travel great distances in relative safety on religious pilgrimages, rely­ing on food and lodging at local monaster­ies along the way. Typically, the only major problem they encountered was communi­cating with each other, or any laypeople they encountered, owing to language differences.

How Chinese forgot language of hand gestures for ‘wet fish’ handshake

Mutually comprehensible hand signals were essential, and a complex non-verbal system, based on the Buddhist mudras, or symbolic philosophical gestures, gradually evolved. The sight of robed monks waving their hands at each other in various gesticula­tions, aided by intermittent smiles, grunts and random words, became a familiar one, especially around Buddhist pilgrimage sites.

As a method of communication, Buddhist hand signals functioned much like Latin, which formed the common language of the educated classes in medieval and early-modern Europe, essentially excluding everyone except priests and monks. Through basic spoken Latin, Germans could commu­nicate with Spaniards, Swedes with Neapolitans, as well as each other, wherever they met. In Catholic Europe, ordinary people knew only a few phrases, mostly responses to the Mass. A passing villager, on hearing two monks babbling away in what he recognised as Latin, would know only that it was an arcane priestly language, and understand virtually nothing else.

Likewise, Buddhist lay people in China knew some of the mudras by sight. As in Europe, criminals or political dissidents could easily disguise themselves as wandering monks. When clad in a uniform robe, with shaven head, shoulder bag and begging bowl, one monk looked much like any other, making it a useful disguisefor anyone trying to evade detection. At a time when most people (especially in rural areas) seldom travelled more than a few miles from home, a passing “monk” on a pilgrimage was a plausible figure who attracted little notice.

Hand signals also aided clandestine recognition among Chinese secret-society members. During the early Qing period, Ming loyalist political dissidents developed their own variations, which could be inserted into an otherwise innocuous sequence to pass hidden messages and indicate which particular faction they supported.

Other functions eventually evolved. Concealed hand signals allowed two parties to negotiate business trans­actions when surrounded by others who may have wanted to know what was happening, either for commercial reasons or gossip. Long, loose, flowing Chinese sleeves could be used to conceal hand signals during a bargaining session while faces remained as impassive as humanly possible.

A complex series of touches, pinches and pressure points concealed the ups and downs of a negotiation. Until recent years, Chinese businessmen would usually speak to those around them with their hand cupped over their mouth; some­times this gesture was deployed to disguise unpleasant teeth, but most often it was to prevent lip-reading by commercial rivals or ill-wishers.

In steady decline for decades, hand signals are still used from time to time in Hong Kong. These days, however, such gestures are more familiar to triad movie aficionados than the general public.