Instrumentalism is the philosophical claim that the importance of beliefs is their usefulness—their role as instruments—and not in whether the subject of the belief literally exists. Under this concept, the main value of any action or perspective is its practical effects, not any transcendent or universal ideal.
Various forms of instrumentalism imply that “truth” applies to beliefs only marginally, if at all. Instrumentalism usually categorizes beliefs alongside abstractions such as “the number nineteen” or “a typical apple,” which refer to some semblance of reality, even if they don’t have a literal material presence. Some “hard” instrumentalists imply that beliefs are entirely unreal. Anything that is not directly observable, according to instrumentalism, is of dubious reality.
To some extent, philosophical instrumentalism is the suggestion that “the ends justify the means”; not in a moral or ethical sense, but pragmatically. This suggests that the main value of any belief what it drives a person to do. The “truth” of such a belief, in that sense, is irrelevant, and all that matters on a small scale is that belief “A” leads to result or action “B.”
Another application of instrumentalism suggests that scientific theories or theoretical models are meaningful insofar as they generate accurate predictions or consistently explain observations. Under this view, whether a theory such as evolution by natural selection is “literally true” is irrelevant to whether evolution by natural selection is a reliable model for scientific study.
Scripture does not speak of instrumentalism itself. However, Jesus criticized the Pharisees for pursuing traditional rituals for their own sake (Mark 7:8). The book of Hebrews points out that the ultimate purpose of certain Mosaic laws was to imply a higher meaning (Hebrews 8:5). And, of course, the Bible in no way supports the suggestion that ends are sufficient to justify means. On the other hand, Jesus frequently taught that God’s laws were not meant to be followed with mindless literalism (Matthew 12:1–8), which parallels the instrumentalist view that practical outcomes are part of how behaviors are assessed. Overall, Scripture at least contradicts the more strident forms of instrumentalism.