By Noam Chomsky. New York: Mouton de Gruyter, 2004

Principles and Parameters

Under the P&P approach, acquisition is entirely divorced from the format for I-languages provided by UG, which in turn reduces to fixed principles and parameters (their values to be set by experience). (xi)

Paraphrase of Chomsky’s Statement

In the Principles and Parameters framework, the process of acquiring a language (acquisition) does not rely on learning the format of internal language structures (I-languages), because that format is already determined by Universal Grammar. UG consists of a fixed set of universal principles, and a finite set of parameters whose values are determined through linguistic experience.

Explanation:

Chomsky himself did not publish a definitive, complete list of all the principles and parameters of Universal Grammar (UG). Instead, he proposed that UG must contain such a set — in principle — and left the task of identifying them to ongoing linguistic research. Chomsky's P&P theory is a theoretical architecture, not a fully enumerated list. He viewed UG as a kind of hypothetical mental organ

He did suggest examples, but never claimed the list was exhaustive.

Fixed in Thoery:

Chomsky's Principles and Parameters (P&P) model assumes that:

• There exists a fixed, finite set of universal principles and binary(-like) parameters in the human mind.
• These are innate (part of our biological endowment as humans).
• The system is shared by all humans, regardless of the language they grow up speaking.

In this sense, the system is fixed in principle, like a kind of "mental grammar engine" embedded in the human brain — the variation we see among languages just reflects different parameter settings.

This is what gives the model its explanatory power: a small, fixed set of options can account for a vast range of language diversity.

Open in real-world: However, in real-world linguistic research, the actual list of principles and parameters has turned out to be:

1. Incomplete – No one has identified the full inventory.
2. Evolving – Some proposed parameters have been revised, reinterpreted, or abandoned.
3. Controversial – Researchers debate whether some language features are due to parameters or to other factors (e.g., processing, usage frequency, morphology).
4. Language-specific complications – Some languages show variation that doesn’t fit neatly into binary parameters.