The Difference Between Rational and Action Models

Designing has been described as the process through which a structure or component is designed. A design is actually a blueprint or detailed description of an object or system, or even for the successful execution of a specific action or procedure, or the outcome of that particular plan or specification in the shape of a model, implement or product. The word ‘design’ itself thus refers to a formal process by which a particular object is produced. The verb ‘design’ thus indicates the active process of designing. Other related English words and terms used are ‘decided’, ‘designed’ and ‘made’.


Designs generally have one of two forms: those that have been designed and are being put into practice and those that have been designed but are not yet implemented or are done in a specified form. A number of innovative designers make use of the word ‘implemented’ to describe designs in progress. This is useful in presenting data and interpretations of design processes for decision-making purposes. The problem with this approach, however, is that it implies the presence of some problem-solving abilities and capacities and implicitly assumes that these are necessary prerequisites for problem-solving. Designers who do not assume the existence of problem-solving skills and potentials in designs may find their designs insufficient to satisfy the needs of clients. Some designers may also apply the concept of designing to mean the completion of a set of activities designed to achieve some goal or intended effect.

This article presents a rational model for designing incorporating both rational expectations and problem-solving skills. The rational model consists of three components. These are the component which is the actual, existing, or planned structure or object, and the component which is the rational model of that structure or object. In the first component, we consider the design specifications and requirements, together with the corresponding descriptions or data, in order to determine the extent to which they incorporate rational expectations. In the second component, we consider the logical or theoretical foundation for designing, together with the assumptions and modeling procedures needed to determine the degree to which they incorporate rational expectations.

With the rational model, one can begin designing by defining and documenting architectural and technical specifications. The documentation should specify the expected end result, and the manner in which that result will be achieved. It should also define the actions required to achieve that end. After defining the specification and actions necessary in the design process, one can move on to the first component of the rational model of the designed object.

The term “designed” refers to the fact that a structure or object has been designed, and at the same time the structure or object is being put into use. At this point, some designers, acting on the basis of rational models, turn to engineering design in an attempt to provide a more satisfactory result. The difference between “designed” and “engineered” is that “designed” refers to the fact that work is being done with respect to certain objectives, whereas “engineered” is to the effect that the objectives have been deliberately made. Some designers use both terms interchangeably, and some designers believe that they are used interchangeably because both terms refer to the planning or design stage of the process. However, an important distinction is between the rational model and the action-oriented perspective. When an individual uses the rational model, she is describing an object as it exists in reality, whereas when an individual uses the action-oriented perspective, she is describing an object as it would exist under specific circumstances.

Architectural Design is based upon rational models and the actions that can be taken in a particular situation to ensure the achievement of the design objective. An action-oriented perspective places emphasis on engineering design and is characterized by what is called the systematic approach. This perspective believes that the goal of the project is to create a system rather than an item, and this system should be well understood by the people who are carrying out the design process. Many architects believe that an action-oriented project has a much higher chance of success because it requires a more systematic approach than a rational model. This is because the systematic approach allows the architect to consider many different factors affecting the design process.