What is a 'Bridge' Concept?
… concepts which have proved useful for ordering things easily assume so great an authority over us, that we forget their terrestrial origin and accept them as unalterable facts. They then become labeled as ‘conceptual necessities’, ‘a priori situations’, etc. The road to scientific [and moral] progress is frequently blocked for long periods by such errors. It is therefore not just an idle game to exercise our ability to analyze familiar concepts, and to demonstrate the conditions on which their justification and usefulness depend, and the way in which these developed […]. In this way, they are deprived of their excessive authority.
Scientific knowledge plays a very important role in our society. Why is it so? The assumption is that science is the paradigm of (empirical) knowledge and, as such, scientific claims have a certain authority. These claims overcome the level of opinions and they capture some objective facts about the world.
But, in perhaps less obvious ways, this role is also based on the successful integration of scientific concepts in ethical and social debates. The success of such scientific concepts can be partly explained by the fact that they combine a certain epistemological objectivity and a normative valuation standard, they provide a bridge between the realms of “is” and “ought.” Scientific concepts are based on an objective foundation since they are supposed to capture (subject-independent) facts and patterns about the world. At the same time, these concepts have also been invested with normative force and treated as proxies for values. For example, when the doctor tells you that your heart surgery went well, and now you are healthy, she is making a scientific, statistical judgment (a value-free judgment) about the normal functioning of your organ, but also, and maybe even more importantly, she is telling you that this state of affairs is good for you. She is also making a normative or an evaluative judgment. So, this category of concepts, which includes ‘health’, ‘fitness’, ‘advantage’ or ‘well-adaptedness,’ seems to track a set of objective values.
The conceptual benefit of bridge concepts lies in their capacity to overcome both relativism, which sees values as determined by specific forms of culture and history, and reductionism, which reduces some scientific claims to statistical judgments (statistical outriders in case of sick people). The concept of health can be both “based on an empirical biological foundation and be evaluative” (Lennox, 1995, p.499) at the same time. There is a sense in which certain features of life provide an objective validation for a certain class of value concepts. Whenever they are employed, they provide more than an empirically observable description of reality. They also always come with an implicit normative connotation.
This class of concepts is especially effective when it comes to values assigned to nature, such as conservation values. Over the last century, conservation policy and practice has relied on a series of concepts drawn from the science of ecology, including the balance and harmony of nature, ecosystem health and integrity, ecological interdependence, keystone species, and so on. Each one of those concepts has been the center of significant research attention and criticism at the same time. In my next post, we will analyze the importance of such a bridge concept - biodiversity.
Lennox, J. 1995. Health as an Objective Value. Journal of Medicine and Philosophy. 20: 499-511.