1 The four principles

The four principles. The four principles of freedom, security, justice and efficiency underlie the whole of the DCFR. Each has several aspects. Freedom is, for obvious reasons, comparatively more important in relation to contracts and unilateral undertakings and the obligations arising from them, but is not absent elsewhere. Security, justice and efficiency are equally important in all areas. The fact that four principles are identified does not mean that all have equal value. Efficiency is more mundane and less fundamental than the others. It is not at the same level but it is nonetheless important and has to be included. Law is a practical science. The idea of efficiency underlies a number of the model rules and they cannot be fully explained without reference to it.

At one level, freedom, security, and justice are ends in themselves. People have fought and died for them. Efficiency is less dramatic. In the context of private law, however, these values are best regarded not as ends in themselves but as means to other ends — the promotion of welfare, the empowering of people to pursue their legitimate aims and fulfil their potential.

In preparing the first part of this account of the role played by these underlying principles in the DCFR, we have drawn heavily on the Principes directeurs du droit européen du contrat1.and we refer the reader to the analytical and comparative work done in their elaboration. However, we have had to take a slightly different approach for the purposes of the DCFR, which is not confined to traditional contract law.

It is characteristic of principles such as those discussed here that they conflict with each other. For example, on occasion, justice in a particular case may have to make way for legal security or efficiency, as happens under the rules of prescription. Sometimes, on the other hand, rules designed to promote security have to be balanced by considerations of justice, as happens under the rules in Books V and VI which allow for a reduction of liability on equitable grounds. Freedom, in particular freedom of contract, may be limited for the sake of an aspect of justice — for instance, to prevent some forms of discrimination or to prevent the abuse of a dominant position. Principles can even conflict with themselves, depending on the standpoint from which a situation is viewed: freedom from discrimination restricts another's freedom to discriminate. One aspect of justice (e.g. equality of treatment) may conflict with another (e.g. protection of the weak). Therefore the principles can never be applied in a pure and rigid way.

The principles also overlap. As will be seen below, there are many examples of rules which can be explained on the basis of more than one principle. In particular, many of the rules which are designed to ensure genuine freedom of contract can also be explained in terms of contractual justice.