REASON, FAITH AND SCIENTIFIC
PROOF
SCIENTIFIC EVIDENCE
AND REASONABLE FAITH IN RELIGIOUS CONTEXT
Stes de Necker
Scientific Proof
Scientific Evidence
The
phrase “scientific evidence” has become part of the vernacular – thrown about
like a hot potato during discussions of major environmental, health,
social
and religious issues.
Scientific evidence is evidence which
serves to either support or counter a scientific theory or hypothesis.
Such evidence is expected to be empirical evidence and interpretation in
accordance with scientific method.
While the phrase "scientific
proof" is often used in the popular media, many scientists have
argued that there is really no such thing. For example, Karl Popper once
wrote that "In the empirical sciences, which alone can furnish us with
information about the world we live in, proofs do not occur, if we mean by
'proof' an argument which establishes once and for ever the truth of a
theory,".
We’ve
heard numerous mentions of “scientific evidence”, indicating the importance
of the issue and the need for action. This evidence is presented by proponents
in much the same way that evidence is given in a court case, usually to back up
policies or decisions that will impact people’s lifestyles. But, unlike in a
court case, we are rarely told exactly where the evidence comes from and why it’s
evidence.
In summary, a scientist creatively develops
a theory which may be falsified by testing the theory against evidence or known
facts. In contrast, evidence cannot prove a theory correct because other
evidence, yet to be discovered, may exist that is inconsistent with the theory.
Standards for scientific evidence vary
according to the field of inquiry, but the strength of scientific evidence is
generally based on the results of statistical
analysis and the strength of scientific controls.
Scientific
evidence however relies on data, and it is crucial for
researchers to ensure that the data they collect is representative of the
“true” situation. This means using proved or appropriate ways of collecting and
analysing the data and ensuring the research is conducted ethically and
safely.
Take for
instance the
recent neonicotinoid
issue.
If a
researcher wants to prove that use of a pesticide does not affect
bees flying about in the environment where the chemical is normally used, they
will need to test two different scenarios.
One
hive of bees will have to go about their business out in the field while being
exposed to the pesticide. A second hive of bees will have to be in the same
general environmental location as the first hive (to ensure both hives
experience the same overall living conditions), but remain completely
uncontaminated by the pesticide throughout the test.
It’s
obvious how impossible this would be to manage under natural conditions, where
no one can control the drift of chemical droplets or the movement of tiny
insects across the landscape! In this case, completely field-based studies may
not exist, but it would be misleading to say that a “lack of field studies”
means that the pesticide does not affect bees.
Absence
of evidence is not evidence of absence!
Background Beliefs
A person's assumptions or beliefs about the
relationship between observations and a hypothesis will affect whether that
person takes the observations as evidence. These assumptions or beliefs
will also affect how a person utilizes the observations as evidence.
When rational observers have different
background beliefs, they may draw different conclusions from the same
scientific evidence. For example, Priestley,
working with phlogiston theory, explained his observations
about the decomposition of mercuric
oxide using phlogiston. In contrast, Lavoisier,
developing the theory of elements, explained the same observations with
reference to oxygen. Note that a causal relationship between the
observations and hypothesis does not exist to cause the observation to be taken
as evidence, but rather the causal relationship is provided by the person
seeking to establish observations as evidence.
A more formal method to characterize the
effect of background beliefs is Bayesian inference. In Bayesian inference,
beliefs are expressed as percentages indicating one's confidence in them. One
starts from an initial probability (a prior),
and then updates that probability using Bayes'
theorem after observing evidence. As a result, two
independent observers of the same event will rationally arrive at different
conclusions if their priors (previous observations that are also relevant to
the conclusion) differ.
The importance of background beliefs in the
determination of what observations are evidence can be illustrated using deductive reasoning, such as syllogisms. If
either of the propositions is not accepted as true, the conclusion will not be
accepted either.
Philosophic versus scientific views
of scientific evidence
The philosophical community has
investigated the logical requirements for scientific evidence by examination of
the relationship between evidence and hypotheses, in contrast to scientific
approaches which focus on the candidate facts and their context.
Bechtel,
as an example of a scientific approach, provides factors (clarity of the data,
replication by others, consistency with results arrived at by alternative
methods and consistency with plausible theories) useful for determination of
whether observations may be considered scientific evidence.
There are a variety of philosophical
approaches to decide whether an observation may be considered evidence; many of
these focus on the relationship between the evidence and the hypothesis.
Carnap recommends distinguishing such
approaches into three categories: classificatory (whether the evidence confirms
the hypothesis), comparative (whether the evidence supports a first hypothesis
more than an alternative hypothesis) or quantitative (the degree to which the
evidence supports a hypothesis).
Achinstein
provides a concise presentation by prominent philosophers on evidence,
including Carl Hempel (Confirmation), Nelson
Goodman (of grue fame), R. B.
Braithwaite, Norwood Russell Hanson, Wesley C.
Salmon, Clark Glymour and Rudolf Carnap.
Based on the philosophical assumption of
the Strong Church-Turing Universe Thesis, a
mathematical criterion for evaluation of evidence has been conjectured, with
the criterion having a resemblance to the idea of Occam's Razor that
the simplest comprehensive description of the evidence is most likely correct.
It states formally, "The ideal
principle states that the prior probability associated with the hypothesis
should be given by the algorithmic universal probability, and the sum of the
log universal probability of the model plus the log of the probability of the
data given the model should be minimized."
This philosophical belief in
"hypothesis testing" as the essence of science is prevalent among
both scientists and philosophers. It is important to note that this hypothesis does
not take into account all of the activities or scientific objectives of all
scientists.
Faith and reason
Since
the early days of Christianity, there were two clearly identifiable streams
present, namely those who practiced an essentially existentialist faith and
those who accentuated the reasonable aspect of their belief.
Today,
more than before, it is a great challenge for Christians to integrate their
faith with ‘scientific proof’.
An
existentialist faith
What
is existentialist faith? It a trust in God which is practiced and experienced
in all aspects of daily life.
This
faith normally flows from a particular commitment to God. For such believers,
this is a way of life - spirituality is at the center of their whole existence.
For them it makes little sense to speak about spirituality if you do not
experience it. Since most of these existential believes do not accentuate reason
- for them it is not really important what science thinks!
An
intellectual belief
What is "intellectual belief"? This is a set of religious convictions which grow out of intellectual reasoning.
What is "intellectual belief"? This is a set of religious convictions which grow out of intellectual reasoning.
During
earlier epochs, when the ancient worldview were still prevalent, intellectual
Christians used reason not only to formulate their belief, but also to argue
for it against the prevalent non-Christian views of the time. Many of the early
Christian fathers were educated in Greek philosophy.
This
lead to the rise of Christian philosophy - especially of the Augustinian
(derived form Platonic philosophy) and Thomist (referring to Thomas Aquinas and
derived from Aristotelian philosophy) varieties.
With
the rise of science - the rational-empirical study of things which requires
physical proof - it became clear that it is impossible to proof the existence
of God.
But
the philosopher Immanuel Kant (1724-1804), himself a Christian, argued that
there are certain limits to pure reason - that is, to what extend pure reason
can arrive at real (empirical) knowledge.
And
this allows for faith to exist next to science. Although we could rationally argue for
our faith, we will never be able to proof it in any scientific sense.
For
the intellectual Christian it is nonetheless important to find a rational basis
for his or her faith.
They
do not have a problem to accept the basic scientific views about the world,
although they reject the view that science have (or will ever have) all the
answers.
For many believers, "scientific
belief" is
in some sense the balance between faith and reason.
A
reasonable faith
It seems that the most rewarding form of religious life is when science, faith and reason are fully part of our lives. It is not only rewarding in the sense that such a person can experience the joy of practical faith in the framework of intellectual integrity.
It seems that the most rewarding form of religious life is when science, faith and reason are fully part of our lives. It is not only rewarding in the sense that such a person can experience the joy of practical faith in the framework of intellectual integrity.
Although
we understand that all human knowledge is partial and temporary, we also know
that people's intellect require convincing them of the trustworthiness of religious
faith.
At
the same time, their spiritual needs require a grounding in practical faith.
With
intellectual growth comes freedom from all the many rules and regulations of
legalistic faith, but this freedom is contained within the boundaries of a
spiritual relationship with God. With spiritual growth comes the deeply
personal intuitive knowledge of God that enables us to overcome and be
victorious in all circumstances.
As we
develop our own perspectives, the potential for conflict with long-held
communal views will force us to involve others in our own process of growth -
some will resist these perspectives, but others will accompany us on the
way.
Reason and intuition
(faith is intuitive trust) are not disconnected faculties - they are
interconnected in a fundamental way, so that their development and integration
into a balanced harmony forms part of the process of intellectual growth.
It is only when both
the intellect and the inner intuitive experience of God are synthesized, that
the ideal of the religious person, who is both "wise" and
"spiritual" can be realized.