Abstract

In an earlier book, Practical Induction, I used a transcendental argument to show that we have to learn what matters from experience: that inductive inference about what is important and worth doing really is inference. Now, this is a claim about logic, and that very fact prompts second thoughts. Can transcendental arguments really establish conclusions about logic and about rationality more generally? So testing whether it’s possible to produce similarly structured arguments for results about theoretical rationality is a reality check on those earlier conclusions. Hard Truths is meant in the first place as such an argument. Its central conclusion, established transcendentally, is that when we reason about how the facts stand, we have to deploy premisses and other steps in our trains of thought that we understand to be kind of true, sort of true, true enough, etc., but not fully true. Partial truth cannot be given the sort of uniform formal treatment to which contemporary theories of vagueness aspire. Bivalence – a guarantee of full-fledged truth or falsity – is normally a local phenomenon produced ….