Jeffrey Thayne

In my previous post, I explained how experimentation is essentially a kind of logical argument. Based upon this assumption, I demonstrated how experimentation alone could never indubitably prove a hypothesis true, because whenever we conclude that our theory is true on the basis of observation, we have committed a logical fallacy known as affirming the consequent.

A philosopher of science known for pointing this out, Karl Popper, presented an alternative view of science, which is sometimes referred to as falsificationism. Rather than prove things true, he said, experiments should be designed to prove things false. The logical argument could be laid out like this:

If theory x is true, we will observe y.
We do not observe y.
Therefore, theory x is not true.

The logic of this syllogism is valid; there are no fallacies here. Thus, science would be useful for discarding false theories, one by one. From this point of view, there are no theories proven true; only theories that have yet to be falsified. This change of rhetoric avoids the logical mess of verification.

Popper’s point of view, however, is not without problems. Brent Slife and Richard Williams explain:

The strategy of falsification will not work unless we are sure that our test or experiment is the crucial test of the theory or hypothesis. No experiment will be a crucial test unless all possible variables (or limiting conditions) have been controlled or taken into account. There must be no other possible explanation for the failure of the experiment except the falsity of the hypothesis. This degree of control is, of course, impossible—practically and in principle. There are, in principle, an infinite number of things to be controlled in order to falsify any theory or hypothesis. Not all of them can be controlled, if only because there is no control over the particular point on the space-time continuum where any study is conducted—that is, each study is conducted as a particular place and time. Consequently, the effects of that particular context can never be controlled experimentally. [This space-time challenge is negated if you assume that time and space are homogenous, but that is an assumption, not an indubitable or demonstrated truth]1

In other words, “the methods of empirical science cannot falsify theories or hypotheses. This has been well recognized among philosophers of science (e.g., Lakatos, 1970).”1

As I explained in my previous post, my purpose here is not to dismiss science. I am not claiming that science is untrustworthy. My only claim is that the trust we have in science is not the inevitable result of the particular methods science uses. Many philosophers of science will agree that no method can be the royal road to truth; in other words, that there is no systematic way to obtain indubitable knowledge. “Whatever scientific methods may be good for,” Slife and Williams explain, “they cannot be used to verify theories, in the sense of affirming the consequent, or falsify theories, in the sense of negating the consequent.”1

This does not mean that science should have no persuasive power; I think we ought to be persuaded by well-performed, systematic, and thoughtful scientific experiments. Science is just that: a useful means of persuading people to understand the world in a particular way. I just don’t believe that science represents the progressive march towards truth that many people interpret it to be. Science may certainly unify us into a collective worldview, and persuade us to embrace a particular point of view. It isn’t, however, the road to certain truth.

In my next post, I will address why logic and reason are persuasive to us. I will also discuss a new way of understanding science that doesn’t involve the logical problems discussed in these posts.

1. Brent Slife and Richard Williams, “Science and Human Behavior”, in What’s Behind the Research? Discovering Hidden Assumptions in the Behavioral Sciences (Thousand Oaks, CA: SAGE Publications, 1995), pp. 167–204.