Changing the rules to protect a conclusion

A claim should be open to examination under standards that do not change simply because the evidence becomes inconvenient. We can revise a claim when we learn more, but a revision should improve its accuracy rather than make it impossible to challenge.

This lesson examines special pleading, moving goalposts, “no true Scotsman,” ad hoc rescue, and unfalsifiable empirical explanations. These patterns differ in how they protect a favored conclusion from a fair test.