modalscience.pdf
The objective modality, such as metaphysical modality, nomic modality or immediate practical modality, is a important concept which is different from subjective modality. And the modality in science is especially confusing. Because the core language of science is mathematics which is no need of necessity and possibility, the statements in science always mislead us that there is no modality in science. But what we should notice that actually modality plays an endogenous role in science and if we research it in detail, we will find the hidden modality.
There is a starting case inspiring us that the modality in science, namely laws support counterfactuals. Due to the extra sense in subjunctive conditionals, we may consider that the existence of modality in some statements on laws of nature.
To make it more clear and accurate, Prof. Williamson use some concept trying to describe the real aspect of modality in science. Objective probability is what we should concern because it’s a kind of quantification of the possibility. After that, inspired by the idea of dynamic systems, Prof. Williamson gave the formal semantic to his new language which describes a dynamic system of possible worlds. Modality is involved in the system on account of that the language talks about the possible history and future.
Anyway, modality in science is something is quite different from the logical modality and may have vague relation with metaphysical modality. If we really want to clarify it, we should separate it from our natural scientific knowledge which is too tightly integrated with the rest of our scientific knowledge.
B. Chen Q: What is the relation between logical necessity and metaphysical necessity? And under what conditions one could imply another?
T. Williamson A: There is definitely some relation between them. And Prof. Williamson gave a brief identical transformation from logical necessity to metaphysical necessity.
B. Zhou Q: Is there a axiom system of the language?
T. Williamson A: Not yet. And actually if we try to construct the axiom system, it should be very complicated but it could be done in theory.
The topic Prof. Williamson talked about is macroscopic involving many fundamental fields in metaphysics, logic, language and science and even certain relations between the. We should find out the modality actually hidden under the surface of natural laws and clarify the kind of such modality, which would benefit the epistemology in our knowledge about physical world.
(Edited By X. Su)
