One word for green and blue: do its speakers see colour differently?

Which comes first, thought or language?

• Piaget: language depends on thought. Thinking develops first; language comes later to express it.
• Children who could not yet conserve were taught words like "longer" and "fatter". The words alone did not help them conserve: the concept must come first.

Can your language shape your thinking?

• The Sapir-Whorf hypothesis: thinking depends on language. It comes in two strengths.
• Linguistic determinism (strong version): language limits thought. With no word for something, you can't think about it.
• Linguistic relativism (weak version): language influences thought. Words make some things easier to notice, sort and remember.
• So two people whose languages divide the world differently may see it a little differently.

Evidence from colour and memory

• Recall of events: Whorf claimed Hopi (another Native American language) had no words for time, so speakers thought about events differently. Later linguists found Hopi has many ways to talk about time.
• Labels change recall: people redrew the same simple sketch to match the word they had heard with it.

A bee dances and the hive finds new flowers. Is that language?

Why animals communicate

• Animal communication is passing information between animals of the same species.
• It serves a small set of functions:

• These functions are limited: animal signals are about these basic needs, here and now.

How the bee dance works

• A bee that finds food dances on the comb in the hive. Others follow it, then fly to the food.
• Round dance: circling, when food is near.
• Waggle dance: a figure of eight with a straight "waggle run", when food is further away.
• Direction: the waggle run's angle from straight up matches the angle between the food and the sun.
• Distance: the longer the waggle run, the further the food.

What human language can do

• Humans communicate about anything, not only survival, mating, territory and food.
• Displacement: talking about things not present, in the past or the future. You can plan ahead and discuss next week's party.
• Creativity (productivity): making endless new sentences nobody has said before.
• Animal signals are a fixed set about the here and now. A bee can't tell the hive about yesterday's flowers.

Stand too close to a stranger and they step back. Who set the gap?

Saying it without words

• Verbal communication uses words, spoken or written.
• Non-verbal communication (NVC) sends messages without words.
• Main types: facial expressions, eye contact, body language (posture, gestures, touch) and personal space.
• NVC often says more about feelings than words do, e.g. a "fine" said with a frown.

What eye contact does

• Regulating the flow of conversation: speakers look away as they start talking, then look back at the listener as they finish, signalling "your turn".
• Signalling attraction: we look more at people we like, and our pupils widen.
• Expressing emotion: a long stare can show anger; avoiding eye contact can show embarrassment or sadness.
• Without eye contact (e.g. talking to someone in dark glasses), conversations have more pauses and interruptions.

Body language

• Open posture: arms and legs uncrossed, relaxed; signals friendliness and acceptance.
• Closed posture: arms folded or legs crossed; can signal disagreement or defensiveness.
• Postural echo: copying the other person's posture. It signals rapport, and people tend to like those who echo them.
• Touch: a light touch on the arm can make someone more positive towards you, but rules about touch vary between cultures.

Personal space

• Personal space is the area around you that feels like yours; uninvited entry feels uncomfortable.
• Hall's approximate zones: intimate (up to 45 cm), personal (45 cm to 1.2 m), social (1.2 m to about 3.6 m) and public (beyond that).
• Culture: comfortable distances differ. In many Latin American cultures, friends stand closer than is usual in the UK or Northern Europe.

Status and gender

• Status: people of similar status stand closer together; we keep more distance from someone of higher status, such as a head teacher.
• Gender: on average, men keep a larger personal space than women.
• Men tend to dislike someone sitting directly opposite them; women tend to dislike someone sitting beside them.

Babies born blind smile. Why do cultures read one face differently?

Darwin: expressions evolved

• Darwin (1872) said facial expressions and other non-verbal signals evolved because they were adaptive: they helped our ancestors survive and reproduce.
• Genes for useful signals were passed on, so the signals became innate (inborn) and universal.
• Example: baring the teeth began as getting ready to bite. It became a signal of anger that can warn off an attacker without a fight.
• A baby's smile and cry win carers' attention.

Evidence that NVC is innate

• Neonates (newborn babies) smile, cry and pull a disgust face within days of birth, before they could have learned them.
• Sensory deprived: children born blind smile, frown and cry like sighted children, though they have never seen a face.
• Athletes blind from birth made the same expressions as sighted athletes when they won or lost.
• Some expressions (e.g. happiness, sadness, anger, fear, disgust, surprise) are recognised across many cultures.

Evidence that NVC is learned

• Gestures differ between cultures. A thumbs up or "OK" sign can be friendly in one country and rude in another.
• Cultures have display rules: learned rules about when to show or hide feelings, e.g. hiding disappointment in front of a teacher.
• How people interpret faces also varies with culture. If it were all innate, everyone would read faces the same way.

Big ideas

• Piaget: thought comes first and language expresses it. Sapir-Whorf: thinking depends on language.
• Linguistic determinism (language limits thought) is not supported; linguistic relativism (language influences what we notice and remember) has support from colour studies and studies of Native American languages.
• Animal communication serves a few functions: survival, reproduction, territory and food. The bee dance carries direction and distance, but only about food.
• Human language has properties animal communication lacks, such as displacement (planning ahead, discussing the future) and creativity.
• Verbal communication uses words; non-verbal communication sends messages without them, through eye contact, body language and personal space.
• Eye contact regulates conversation, signals attraction and expresses emotion; open and closed postures signal different attitudes.
• Personal space (Hall's zones) varies with culture, status and gender.
• Darwin: non-verbal signals evolved because they were adaptive, so many are innate and universal.
• Newborns and people born blind show basic expressions without learning them; but gestures, display rules and how faces are read are learned in a culture (Yuki et al., 2007).