Tuesday, February 8, 2011

Scientific Knowledge and Faith


For most people of contemporary Western culture the arbiter of reality, or truth, is probably the enterprise we know as “science.” We understand truth to be that which can be scientifically verified. The word science comes from the Latin scio, “I know,” and science represents for us that which we can know for certainty. But our confidence in science as the uniform guarantor of knowledge might be misplaced.

A typical image of the progress of science pictures succeeding generations of scientists building upon the achievements of their predecessors, verifying their conclusions and correcting their errors. Few people are aware that science, as we understand it today, has not developed in this manner, but instead has evolved through a series of “revolutions” in which the underlying assumptions of the previous era have been called into question. Science has moved forward not by the steady accumulation of data, but by the replacement of old paradigms of understanding with new insights — insights which came not from newly discovered data but from a different way of structuring and interpreting the data already available.

For example, ancient and medieval astronomers operated with Ptolemy’s system in which the earth was the center of the universe. The Polish astronomer Copernicus, however, developed a different paradigm in which the sun, not the earth, was the center. In this heliocentric model, which he published in 1543, the observed movements of stars and planets in the night sky were no longer understood as their movements with respect to the earth, but as resulting from the earth’s revolution about the sun.

At the time there was no real “proof” of Copernicus’s theory, since the observations of astronomers could still be forced into Ptolemy’s geocentric system of epicycles. Copernicus’s system was thought to be an interesting possible alternative to Ptolemy’s, but was no more “scientifically” challenging; thus it failed to generate much controversy when first proposed. A century later, when Galileo invented the telescope, more accurate observations of the night sky provided the data needed to completely call into question Ptolemy’s earth-centered model. It was only then that Copernicus’s system became controversial. This was largely due to a failure, on the part of church leaders, to separate biblical teaching and Christian doctrine from philosophical assumptions on which the old science was based. Eventually, of course, even Copernicus’s heliocentric model had to be abandoned once vastly more powerful instruments revealed the enormous, multi-galactic scope of the universe.

The example of the “Copernican revolution” shows that science evolves not by accumulation of new facts but by the insight of individuals who are willing to question the unproven assumptions of a previous scientific establishment. The history of science is filled with breakthroughs of this sort, such as Isaac Newton’s “laws” of gravitation, or Einstein’s theory of general relativity which modified and replaced them. Einstein’s theory, which suggests that gravity is an effect of the “curvature” of space, is not self-evident to an observer working within the Newtonian four-dimensional structure, which has no place for “curved” space. Scientific advance, then, does not depend on accumulating observations or measurements or copious experimentation within the established paradigm; it depends on the insight of an individual who is able to break out of that paradigm and think about the phenomena of the universe according to a different model. (The classic discussion of this issue is Thomas Kuhn’s The Structure of Scientific Revolutions, first published in 1962.)

The early nineteenth-century French mathematician Laplace developed a theory of causal determinism: if we could know the precise present state of every atom in the universe, we could determine the exact course of past and future cosmic events. A popular view of science might agree with Laplace — would not the knowledge of everything be the key to the solution of all problems, through science? But this “thought experiment” destroys science itself by removing the element of human insight by which scientific knowledge actually moves forward. Therefore, Laplace’s hypothesis is sometimes called “Laplace’s demon.”

The point of this discussion is that science is not a mere objective body of knowledge requiring no personal involvement. Science is simply what scientists do, based on their unproven and unprovable philosophical assumptions about the nature of reality and how it can be known. The scientific enterprise is an exercise in personal commitment, and scientific knowledge is personal knowledge (see Michael Polanyi, Personal Knowledge, 1962). It is, therefore, akin to religious knowledge; like religious knowledge, it depends upon the exercise of faith.

Can the faith of the scientist be correlated with the faith of the Christian believer? If the universe is God’s creation, and if Jesus Christ is “upholding the universe by his word of power” (Hebrews 1:3), then the faith of the Christian and the faith of the scientist must become one. We will explore that thought in future entries.

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