Language learning is a complex process that involves cognitive, social, and academic development. For bilingual students, understanding how knowledge in one language impacts the acquisition of another has long been an important area of study. One of the most influential theories in this domain is Jim Cummins’ Interdependence Hypothesis. This theory offers valuable insight into how a student’s first language can play a significant role in second language development, especially in academic settings. The Interdependence Hypothesis is widely referenced in educational research, bilingual education policy, and curriculum design for multilingual learners.
Understanding the Interdependence Hypothesis
Definition and Origins
The Interdependence Hypothesis, proposed by Canadian linguist Jim Cummins in the late 1970s, suggests that the development of proficiency in a second language (L2) is partially dependent on the level of proficiency already achieved in the first language (L1). According to Cummins, if a student has a strong foundation in their first language, the skills and knowledge gained in that language can be transferred to support learning in a second language.
This theory challenges the earlier notion that learning a new language requires suppressing or replacing the first language. Instead, Cummins emphasizes that the two language systems are interdependent, and progress in one supports development in the other.
Key Components of the Hypothesis
There are two central ideas in Cummins’ Interdependence Hypothesis:
- Transfer of skills: Linguistic and cognitive skills such as reading comprehension, critical thinking, and problem-solving are transferable between languages.
- Threshold level: A minimum level of proficiency in the first language is necessary before effective transfer to the second language can occur.
The Role of Common Underlying Proficiency (CUP)
What is CUP?
Cummins introduced the concept of a Common Underlying Proficiency (CUP) to explain how language skills developed in one language can support another. According to this model, different languages have a shared foundation of knowledge and skills. When students learn concepts or develop literacy in one language, that learning becomes part of their overall cognitive framework and can be accessed in another language.
Practical Implications
For example, if a child learns how to write a persuasive essay in their native language, they have already developed an understanding of argument structure, tone, and organization. When they write an essay in their second language, they do not need to relearn those academic skills they only need to acquire the vocabulary and grammar in the new language to express the same ideas.
Academic Language vs Conversational Language
Basic Interpersonal Communicative Skills (BICS)
In connection with the Interdependence Hypothesis, Cummins also distinguished between two types of language proficiency: Basic Interpersonal Communicative Skills (BICS) and Cognitive Academic Language Proficiency (CALP). BICS refers to the language skills needed for everyday social interactions. These skills are usually acquired within 12 years of exposure to a new language and involve face-to-face communication.
Cognitive Academic Language Proficiency (CALP)
CALP, on the other hand, refers to the more advanced language skills required for academic learning, such as reading textbooks, writing essays, and understanding scientific or mathematical terms. These skills typically take 57 years to develop. The Interdependence Hypothesis supports the idea that developing CALP in the first language helps students succeed in acquiring CALP in the second language.
Implications for Bilingual Education
Benefits of First Language Instruction
The Interdependence Hypothesis has strong implications for bilingual and dual-language programs. It suggests that maintaining and developing the first language can enhance second language learning rather than hinder it. This supports the implementation of programs where students continue academic instruction in their native language while gradually building skills in the new language.
Key benefits include:
- Improved academic performance
- Greater confidence in learning
- Preservation of cultural identity
- Stronger cognitive development
Misconceptions in Language Policy
Some educational systems mistakenly believe that students must abandon their native language to fully acquire a new one. Cummins’ hypothesis directly challenges this by showing that subtractive approaches where one language is replaced by another can negatively impact academic achievement and self-esteem. Additive bilingualism, where both languages are supported, leads to better long-term outcomes.
Research Support and Case Studies
Empirical Evidence
Numerous studies across different countries and educational contexts have supported the Interdependence Hypothesis. For example, research in Canada and the United States has shown that bilingual students who receive instruction in their home language perform better in English over time compared to those who do not receive such support.
Examples in Practice
Dual-language immersion programs in the U.S. have demonstrated the effectiveness of supporting L1 instruction alongside L2 learning. In these programs, students often outperform their monolingual peers in both languages, particularly in reading and writing assessments. These outcomes align closely with Cummins’ theory and highlight the real-world benefits of interdependent language development.
Criticism and Counterarguments
Complexity of Language Transfer
While the Interdependence Hypothesis is widely accepted, some scholars argue that the transfer of skills is more complex than Cummins’ model suggests. They point out that certain linguistic features, such as phonology or syntax, may not transfer as easily between languages that are structurally very different.
Individual and Contextual Differences
Critics also note that individual factors like age, motivation, and exposure to language, as well as educational quality, significantly influence bilingual development. While the Interdependence Hypothesis offers a strong general framework, it may not apply equally to every learner in every setting.
Jim Cummins’ Interdependence Hypothesis continues to be a powerful tool in understanding bilingual education and second language acquisition. By emphasizing the connection between first and second language development, it challenges outdated ideas that view bilingualism as a barrier rather than a benefit. Through the concepts of skill transfer, Common Underlying Proficiency, and academic language development, Cummins provides educators with a framework that supports multilingual learners in achieving their full potential. As global societies become more linguistically diverse, the Interdependence Hypothesis remains highly relevant to shaping inclusive and effective educational policies worldwide.