The background of this approach comes from the classical scientific method which seeks to analyse complex phenomena by looking for explanations at a lower, more basic level. The conceptual model is that of phenomena being like a giant mechanism. The best way of finding out how the mechanism works is to take it to pieces and find how each part functions. Ideally then, all human phenomena would be explained by analysis or reduction to biological phenomena (e.g. war can be explained by animal territoriality and Darwinian survival of the fittest, etc.); all biological phenomena would be analysed down to chemical phenomena (e.g. genetics can be explained by the molecular biology of DNA; animal behaviour by the action of hormones and chemical transmitters, etc.); then all chemical phenomena would be analysed down to physics (e.g. chemical reactions can be explained in terms of the stability of electron orbits around atoms). By a parallel process the complex phenomenon of religion can be analysed down to the more fundamental level of sociology or psychology.
Of course, reductionist scholars will use higher level descriptions but this is only, in principle, either as a shorthand for designating a complex of lower level phenomena or because we do not have as yet sufficient data to enable a full analysis of the phenomenon down to the lower level.
The same approach can be viewed from the opposite direction as maintaining that the lower level phenomena determine the higher level, hence the name determinism. The implication of determinism, if carried to its logical conclusion, is that, since everything at the higher level is determined by what occurs at the lower, all human action is determined. Indeed, if we had sufficient data, it could be predicted. Because the cosmic machine is in motion, everything in the future is already determined and has been from the beginning of time.
Closely linked to analysis is the other aspect of the "scientific approach", empiricism or logical positivism. This is based on the idea that the correct manner in which to proceed is to obtain and assess the facts first and then to evolve by induction from these hypotheses that can be put to the test.
A simple example that is often given is the fact that the combination of Hydrogen and Oxygen yields a substance, Water, the properties of which are not in any way derived from or predictable from the properties of Hydrogen and Oxygen individually. Similarly, no matter how far we have progressed in understanding the behaviour of atoms and sub-atomic particles, this knowledge does not in fact lead to any greater understanding in the field of, for example, animal behaviour or indeed of human behaviour. These higher levels of complexity require their own levels of explanation. Whilst analysis to lower levels of causative explanation may often be useful and even illuminating, these lower levels never in practice fully explain all the features of the higher level of complexity.
A key aspect of this line of thinking is the idea that the higher level phenomena act so as to constrain the lower level phenomena towards certain pathways of action. In other words the direction of causation is downwards from the higher level to the lower. This does not mean that the higher level phenomena cause the lower level phenomena to break the laws that operate at that lower level (the activities of a cat can never cause the atoms of which it is composed to break the laws of physics). It only means that where the lower level phenomena have different possibilities of action, the higher level (i.e. the system as a whole) constrains this choice in one particular direction. This is sometimes referred to as the holistic view as it envisages the system-as-a-whole as being the key operant. This viewpoint is in direct contrast to the determinist viewpoint which sees the direction of causation as being from the lower levels to the higher ones; i.e. that what happens at the lower levels determines what happens at the higher ones.
For scholars who adopt this approach, the key to the study of religion lies in understanding the phenomenon of religion in itself (i.e. at its own level and not by reduction to lower levels). The goal must be to understand the religion or the religious phenomenon in its own terms (i.e. at its own level of complexity) -- to understand how men come to believe as they do and why they act as they do.
Closely linked to this is relativism. This viewpoint opposes the empiricist vision that conceptualises religious data as "given", facts that are seen and agreed upon by all. Relativism stresses that the data can only be seen relative to a particular observer. And so there is no independent or absolute data, only people holding particular views and seeing the world in a particular way.
The contrary viewpoint can be exemplified by the writings of Cantwell Smith who considers that there is no such thing as a neutral academic statement that can be examined in isolation from the scholar who makes it. Every statement is a personal statement, it is made from a particular point of view (and thus potentially reveals as much about the author as about the subject of the statement). Also there are Cantwell Smith's objections to the concept of a religion which he claims is only a reification imposed upon the data (by empiricists). He prefers to think in terms of the religious faith of individuals (i.e. the religious experience relative to the individual) and the ongoing religious tradition.
Those that support the holistic view point out that the analytical/empiricist view of the scientific method is itself outdated. It belongs to the classical Newtonian paradigm which is no longer fully accepted by the scientific community. The Newtonian paradigm tends to be only strictly applicable to regular bodies of intermediate size in closed systems acting in a smooth, regular manner. The way that the Newtonian methods are applied to most real situations (which in practice rarely meet these criteria) is to approximate these to regular systems. This can work to a certain extent but the more complex a system becomes, the less accurate these approximations become. By the time we are dealing with biological and human phenomena, Newtonian methods have become almost useless.
New scientific approaches to complexity and irregularity are being pioneered but these are as yet only in the early stages of development. The important point is that the reductionist, analytical model is no longer seen as appropriate in these studies.
Similarly, the empiricist view can be criticised as it assumes that there are pure facts that can be obtained. Relativity theory, however, implies that there is no such thing as pure facts. All data are dependent on (relative to) the methods used to obtain them. In the field of religious studies this would imply that the data that we collect and study is determined by our theoretical framework. In other words, the data that we collect, far from being the seed from which to derive our theories, as the empiricist tradition would dictate, are themselves theory-dependant.
The empiricists would argue against the holistic view by saying that it leads to meaninglessness. Once one allows for the introduction of high level phenomena and for high level laws to be operating, one can no longer examine phenomena in any systematic "scientific" way. This is because the whole of scientific thought is based upon the idea that a hypothesis is an explanation of a phenomenon that occurs; i.e. it explains at a lower, more simple level the occurrence of a phenomenon. Such a hypothesis should lead to a prediction of further phenomena. Hence it should be possible to verify the hypothesis by seeing whether the prediction is accurate or not.
All of this depends however on the principle of determinism that the lower level phenomena determine the observations one makes of the higher level phenomena. Once one allows that, at the higher level, new laws may begin to operate then the principle of determinism can no longer apply. Any discrepancies from the predictions of the hypothesis could be due to the operation of new laws. The scientific principle of verifiability breaks down. Since, according to logical empiricism, verifiability is the main criterion for cognitive meaning (i.e. only statements that are verifiable, or at least potentially falsifiable, are meaningful), the holistic approach results in cognitive meaninglessness.
The debate will no doubt continue, resurfacing in various guises, for many years to come. In practice, both approaches yield useful and illuminating results. The present writer's inclination is to view both approaches as complementary. In other words that religion is a complex phenomenon, for which new laws emerge at its own level of complexity. These new laws constrain events at the lower level and therefore the phenomenon of religion cannot be fully explained by lower level hypotheses from other fields such as sociology, psychology, economics, etc. But on the other hand these higher level laws only constrain the lower level laws, they do not break them. Therefore an understanding of the lower level laws is also of value. The analogy would be that biology is a complex field and has its own laws that constrain the occurrence of lower level phenomena such as chemical reactions. For example, of the hundreds of ways that a long protein molecule could fold, it is constrained to fold in the only way that would make it have the desired biological activity. However, the laws of biology do not contravene chemical laws. It is, therefore, perfectly legitimate and useful for our overall understanding of biological processes to investigate the manner in which the lower level laws of chemistry affect the biological world.
Peter Berger has used the analogy of the reports of travellers to a far-away country: