If the inference is in accordance with the appropriate rule, it is called valid. Rules of inference are often thought of as the alpha and omega of logic.
Deductive 演绎
- 保持真值 necessarily truth preserving
- 不引入新的信息
Or, rather, we could thus identify deductive inferences as uninformative ones if we had a viable notion of information at our disposal.
Surface information can be characterized as the information that can be read off from a sentence without any nontrivial deductive ado, while depth information is the totality of (surface) information that can be extracted from it by deductive logic. The emergence of new surface information explains why purely deductive inference can be experienced as informative and even productive of surprises
狭义的演绎推理只涉及逻辑常项
Analytic 分析
取决于语句中非逻辑常项的意义的演绎推理，比如「所有单身汉都未婚」。
Ampliative 外推？
Ampliative Argument
Term used by Peirce to denote arguments whose conclusions go beyond their premises (and hence amplify the scope of our beliefs). Inductive arguments and arguments to the best explanation are not deductively valid, but may yield credible conclusions. Most reasoning takes us to conclusions that go beyond our data, in ways that interest us.
Amplifiy → Ampliative
包括所有非演绎的推理形式，如Induction和Abduction
指向原始笔记的链接These sorts of arguments are generally called “ampliative”, because the conclusion says more than is strictly “entailed” by the premises.