Today’s guest post is by Dr. Randy Isaac, former Executive Director of the American Scientific Affiliation, and a good friend. Randy and I share an interest in the concept of teleology in biology, and how notions of purpose and causation might fit into the science faith nexus. Randy also has an excellent article on the subject in this months issue of Perspectives in Science and Christian Faith. In this post Randy, an authority on information science, explains the various meanings of purpose.
The word “purpose” is so common that few people take the time to define it carefully. In contrast, terms like “teleology” and “design” get a lot of attention. More attention needs to be paid to the various nuances of “purpose” as widely used. In this post I consider three distinct usages of the concept of purpose: 1. External agent, 2. Self-determined, and 3. Intrinsic.
1 External agent. The most widely used connotation of “purpose” is a conscious being that ascribes purpose to an object or another being in one of three ways: a. Construction, b. Appropriation, and c. Assignment.
Construction applies predominantly to tools or machines that are designed and built for the purpose of carrying out some task. A hammer, for example, is designed and built to drive a nail into wood. Appropriation refers to a tool or machine constructed for a different purpose but appropriated to do a different task than the one for which it was constructed. A hammer can be used for many purposes other than driving nails. Assignment generally refers to people or animals. Most commonly, an employer asks an employee to serve the purpose of fulfilling some task. Or an animal is trained to carry out a task. In theistic circles, the first thought of “purpose” often refers to God and the purpose in his mind when he created the world, appropriated the laws of nature to carry out his bidding, and his assignment to living plants and animals to be fruitful and multiply and fill the earth. His ultimate purpose for humans is to have dominion over the earth and to serve in his image as children of God.
2 Self-determined. Purpose can also be a goal that a person selects for themselves. One person may decide to make his purpose in life to serve other people in the ministry, others to become a famous scientist, or a successful politician. In religious communities, this role of purpose is often subjugated to the will of God and becomes the guiding principle of life.
3 Intrinsic. Far less frequently and seldom recognized, the word “purpose” can refer to an intrinsic role or function. This is most commonly used in biology. A leaf, for example, has the purpose of collecting sunlight and synthesizing food for the tree as well as exchanging CO2 and H2O. No conscious agent was involved and the purpose is intrinsic to the tree. As biochemists unravel the grand mysteries of cellular processes, the purpose of myriad biomolecules is discovered. However, this use of the word “purpose” is often misunderstood. Without clarification of its use in an intrinsic sense, many people get the impression that biologists are in fact seeing the work of an external agent in setting a purpose for that biomolecule.
A discussion of teleology is most interesting in the context of evolution. The intricate role of so many complex biomolecules is astounding. Purpose is evident everywhere and the conviction is clear that there is some kind of design going on. Is that design merely apparent or is it the action of an external agent? How can one tell the difference? I would suggest that perhaps it is neither merely apparent nor the work of an external agent but the result of intrinsic purpose.
The nature of intrinsic purpose arises in the context of emergence. Philosophers like Phil Clayton, George Ellis, Nancey Murphy, and others are exploring the importance of emergence in contrast to the reductionism which is so prevalent in the scientific community. Emergence refers to the multi-level hierarchy of explanation of the universe. Fundamental levels like atoms and molecules enable higher-level complexity. In turn, these higher-level complexities can constrain or control the action of the atoms and molecules in an exquisite recursive feedback loop. The net result is a system that has intrinsic purpose in the sense of a particular role or function which, in turn, is a component of a larger and even higher-level system.
In this way, purpose and meaning can arise intrinsically in complex systems. The notions of teleology and design need not refer to external agents or involve conscious beings. Intrinsic purpose deserves to be recognized and studied further to understand how teleology exists in biology.

