The classification of a system as complex or simple will depend upon the observer of the system and upon the purpose he has for considering the syste… - Mike Jackson

There exists an alternative to reductionism for studying systems. This alternative is known as holism. Holism considers systems to be more than the sum of their parts. It is of course interested in the parts and particularly the networks of relationships between the parts, but primarily in terms of how they give rise to and sustain in existence the new entity that is the whole whether it be a river system, an automobile, a philosophical system or a quality system.

The traditional, scientific method for studying such systems is known as reductionism. Reductionism sees the parts as paramount and seeks to identify the parts, understand the parts and work up from an understanding of the parts to an understanding of the whole. The problem with this is that the whole often seems to take on a form that is not recognizable from the parts. The whole emerges from the interactions between the parts, which affect each other through complex networks of relationships. Once it has emerged, it is the whole that seems to give meaning to the parts and their interactions. A living organism gives meaning to the heart, liver and lungs; a family to the roles of husband, wife, son, daughter

In the modern systems approach, the concept "system" is used not to refer to things in the world but to a particular way of organising our thoughts about the world.