Coherence and Parsimony

Coherence:1 : the quality or state of cohering : as a : systematic or logical connection or consistency b : integration of diverse elements, relationships, or values

Parsimony: 2 : economy in the use of means to an end; especially : economy of explanation in conformity with Occam's razor

Coherence and parsimony are two "rules of thought" that I sincerely subscribe to. You can say that I have faith in them, even more so than in the divine. I believe that all the facts about the world, including religious statements, must be coherent and parsimonious. That is, I would not believe something, including religion, unless it makes sense by being coherent and parsimonious.

If God is real, then all the facts about religion and about the world must make sense and cohere into one body of knowledge. It cannot be that we believe in the facts about the world in one moment, and then switch and then say that facts about religion are true in another. Another way to say it is that there can only by one reality. The world really exists, as I hope we can all agree, so if God exists, then religious facts heaven, souls and devils for example cannot contradict what we know about the world. They must cohere into one reasonable whole. So if a religion tells me that the earth is the centre of the universe, and we find that it instead revolves around the sun, then one these statements has got to be wrong and must be rejected. Miracles and a loving God involved in the world seem to contradict the laws of physics and the amount of suffering and evil in the world respectively. One of them must be untrue, or at least a reasonable explanation must be given to show why they are not necessarily contradictory.

This brings me to the principle of parsimony. If there exists two explanations to something, then all things being equal, we should accept the simpler one and reject the more complex one. For example I come home and find a window broken and the TV missing. One reason could be that someone broke in and stole it; another is that my TV broke down, my mum took it to repair, and somehow accidentally broke the window just at that spot as well. Based on the same evidence, we take the more direct evidence. In the same way, science has explained a lot of what used to be mysterious and miraculous. A crucial example is where people used to look at nature and be convinced that the only way such complex and beautiful animals can emerge is through an intelligent creator. Evolution has shown how all that is possible just by random natural processes. Rather than go the roundabout way of saying that God made the world such that evolution will take place and such animals will emerge, it makes more sense to just say that evolution did it. Why take the more complicated reason?

What is the philosophical method?
Philosophy is pretty much
pure thinking. And styles of thought have changed quite a lot from one era to
another. I teach a course for doctoral students where I look at the history of
the development of the idea of what is philosophical method? And 10 weeks is not
enough to cover all of that. There have also been big changes in theology. Some
people would say that theologians merely interpret the content of the
scriptures, others say that theology is a discipline that reflects on human
religious awareness, and some of us would say that you've got to be doing both
of those all the time. But my own entree into the theological field was taking
my background in philosophy of science and asking, "What are the parallels in
theology?" And of course the data have to be different, just as the data for
biology are different from the data for physics. But what I was able to argue is
that the structure of reasoning is the same, or at least could be the same in
those two radically different kinds of disciplines. You're forming hypotheses to
try to explain the data in the most coherent and parsimonious way in both cases.



Occam's razor
Pronunciation:
'ä-k&mz-
Function: noun
Etymology: William of Occam
: a
scientific and philosophic rule that entities should not be multiplied
unnecessarily which is interpreted as requiring that the simplest of competing
theories be preferred to the more complex or that explanations of unknown
phenomena be sought first in terms of known quantities