The Knowledge Machine: How Irrationality Created Modern Science

by Michael Strevens

As far as the iron rule is concerned, argument and reasoning are two quite separate things. Reasoning is what scientists do in their heads to get from the outcomes of tests to opinions, convictions, and plans of action. It is how they make up their minds whether some theory is surely false, likely true, or still up in the air. It is how they decide whether some research program is staid, foolish, or risky but bold. It is how they determine for themselves whether a therapy or experimental procedure is reliable, hopeless, or simply unproved. Vital to such thinking are plausibility rankings, which supply the auxiliary assumptions on which all scientific reasoning is based. It is because plausibility rankings are essentially subjective that scientific reasoning is essentially subjective. Scientific argument, by contrast, in the sense that matters to the iron rule, is what appears in science’s official channels for broadcasting research, namely, the scientific journals and conference presentations. It is only in such venues, on the printed page and the projected slide, that objectivity is required.