Why Do People Shake Hands? A Greeting Carrying More Than It Looks

The weapon story appears everywhere and traces to no early source stating it. What can be established is that clasped hands appear in ancient art, on Greek funerary reliefs where the gesture marks farewell and connection rather than greeting, and on Roman coins and monuments where joined right hands represent agreement, alliance and good faith, with a specific Latin term for the concept. Assyrian relief shows rulers clasping hands in a treaty context. In each of these the meaning is bond or agreement rather than the disarming of a stranger, which suggests the gesture's core sense is the sealing of a mutual commitment. The routine use of the handshake as an everyday greeting between equals appears to be much more recent, and its spread is frequently connected to Quakers in the seventeenth century, who refused hat-doffing and bowing as expressions of social rank and used a handshake instead precisely because it treats both parties as equal. That account fits the pattern of a gesture moving from ceremony into daily use as hierarchy became less openly performed.

The brief contact carries a surprising amount, which is why it survived and why substitutes felt inadequate:

• •Reciprocity, since both parties do the same thing at the same time, which distinguishes it from bowing where depth encodes relative rank
• •Touch, which is associated with increased cooperation and warmth in experimental work on brief incidental contact
• •Timing and pressure, which are read as confidence, reluctance or aggression, and which vary by culture enough to cause frequent misreading
• •Physical information, with research finding that people sniff their own hands more after shaking, suggesting chemical signals are picked up and sampled
• •Commitment, since the gesture still closes agreements in contexts where no contract is signed, particularly in trades where a handshake remains binding by convention
• •Inclusion or exclusion, since offering or withholding it is a public act with unmistakable meaning

Greeting gestures vary widely and the variation is not arbitrary, since each encodes a different relationship. Bowing in Japan and Korea conveys relative status through depth and duration, allows greeting at a distance and avoids contact. Namaste and similar joined-palm gestures across South and Southeast Asia likewise avoid contact and carry a respectful register. Cheek kissing across the Mediterranean, Latin America and parts of Europe signals familiarity and varies in number and side by region in ways that reliably confuse visitors. Nose touching among Maori and in several Gulf states creates closeness of a different kind. Handshake conventions themselves differ, with expectations about grip firmness, duration, eye contact, the use of the left hand and whether men and women shake at all varying substantially. Several religious traditions include practices restricting physical contact between unrelated men and women, which makes an offered hand a genuine difficulty rather than a discourtesy, and the workable solution generally adopted is to let the other person initiate.

The gesture transmits microorganisms efficiently, which was well documented before 2020, with studies showing substantially greater transfer than from a fist bump or a high five, and hand hygiene campaigns had targeted it for years without effect. The abrupt global suspension of handshaking during the pandemic produced a natural experiment in whether a deeply embedded custom can be replaced, and the answer appears to be that it can be suspended and not easily replaced. Elbow bumps, waves, bows and nods were adopted awkwardly, participants reported them as unsatisfying, and predictions that the handshake would not return proved wrong in most settings within a couple of years. The interesting part is why. A greeting must be unambiguous, mutual and require no negotiation, and improvised alternatives failed on the last point, since every encounter became a small decision about what to do. The return suggests that the cost of coordinating on a new convention exceeded the hygiene benefit for most people, which is a general feature of entrenched conventions rather than anything specific to this one.

The empty weapon hand story is plausible and unsupported, while ancient clasped hands in art mark agreement and alliance rather than greeting. Everyday use between equals is much more recent and is linked to Quakers refusing bows that encoded rank. The gesture is reciprocal, carries touch, timing and even chemical signals, and still closes deals. It was suspended globally in 2020 and no substitute stuck, because greetings must require no negotiation.