Theories of Language Change

• Language changes for various reasons, which can be explained by different theories and models.

Functional Theory

• Language is a tool that evolves to meet the needs of its users.
• Vocabulary changes reflect societal and technological advancements.

Random Fluctuation Theory

• Language change is not always logical, and can be unpredictable, similar to fashion trends.
• Paul Postle suggests the unpredictable nature of language change.

Expressive Theory

• Language is a form of expression that evolves due to the human desire to express experiences in new ways.
• Highlights creativity and innovation in language use.

Historical, Social, and Cultural Change

• Historical events, like the Industrial Revolution, and evolving values, such as the rise of feminism, drive language change.

Substratum Theory

• Language changes through contact with other languages, facilitated by invasion, immigration, or globalization.

External Factors

• Language changes due to outside events
• Examples include the Norman Invasion and the emergence of youth culture in the 20th century.

Internal Factors

• Linguistic reasons can cause language change.
• An example is the clipping of words over time to simplify pronunciation.

Codification

• Words become official through a process.
• Aitchison's PIDC model describes this process:
  • Potential: A need for a word arises.
  • Implementation: The word is coined.
  • Diffusion: The word gains usage.
  • Codification: The word is accepted, and placed in dictionaries.

Stages of Lexical Change

• Innovation: a word is created
• Diffusion: the word spreads

S-Curve Pattern

• Language change is characterized by:
  • Slow initial progress
  • Followed by rapid progress
  • Until a saturation point is reached.

Wave Model

• Change spreads from one part of society (or the country) to another in stages.
• The impact of change decreases with geographical or social distance from the source.

Innovation Stage

• This is when new words are created and coined.

Diffusion Stage

• This is when new words spread through social groups and geographical spaces.

PIDC Model (Aitchison)

• It explains the process a new word undergoes to become part of a language:
  • Potential: A need/desire for a word arises.
  • Implementation: The word is coined.
  • Diffusion: The word is used extensively.
  • Codification: The word is accepted and added to dictionaries.

Lexical Gaps

• New words often fit existing linguistic structures.
• Example: "Pep" (energy) was an abbreviation of pepper, which made sense due to existing words like pip, pop, and pup.

Aston University Research (Jack Grieve)

• Examined 9 billion tweets in the USA to track the spread of new slang, such as "unbothered" and "on fleek".
• Created maps showing the diffusion of slang terms across different regions over time.
• Demonstrates the diffusion stage, where slang spreads geographically from certain centers.

Sapir-Whorf Hypothesis

• Different languages create different ways of thinking.
• Aboriginal languages in Australia use compass points instead of left/right.
• Speakers have excellent geographical knowledge.
• Emphasizes the importance of inclusive language.
• It illustrates how words shape perceptions of others.

Explore various theories that explain why and how languages evolve. These include functional, random fluctuation, and expressive theories. Also covered are historical, social, cultural, and substratum influences.