# Indiscernibility of possible worlds

## What is possible worlds theory?

Definition. A possible world is a complete way things might be. Possible worlds are alternative worlds one of which is the actual world. Philosophers use the notion of a possible world to define and discuss ideas such as possibility or necessity.

## Do merely possible worlds exist?

Possible worlds exist – they are just as real as our world; Possible worlds are the same sort of things as our world – they differ in content, not in kind; Possible worlds cannot be reduced to something more basic – they are irreducible entities in their own right. Actuality is indexical.

## What is the principle of the Indiscernibility of identicals?

Equivalently, if x and y share all their properties, then x is identical to y. Its converse, the principle of the indiscernibility of identicals (also known as Leibniz’s Law), asserts that if x is identical to y, then every property of x is a property of y, and vice versa.

## What sorts of things are possible worlds?

A possible world is a complete and consistent way the world is or could have been. Possible worlds are widely used as a formal device in logic, philosophy, and linguistics in order to provide a semantics for intensional and modal logic.

## Are there infinite possible worlds?

To have infinitely many possible worlds would require infinitely many sets of consistent propositions. Infinitely many sets of consistent propositions would require infinitely many propositions.

## What is Lewis argument for the existence of possible worlds?

86) Lewis’s argument here is: The actual world is not a set of sentences. The actual world is a possible world. All possible worlds are the same kind of thing: one of them is a set of sentences iff they all are a set of sentences.

## What does modal mean in philosophy?

A modal is an expression (like ‘necessarily’ or ‘possibly’) that is used to qualify the truth of a judgement. Modal logic is, strictly speaking, the study of the deductive behavior of the expressions ‘it is necessary that’ and ‘it is possible that’.

## What is modal logic in philosophy?

Modal logic is a collection of formal systems developed to represent statements about necessity and possibility. It plays a major role in philosophy of language, epistemology, metaphysics, and natural language semantics.

## What is actual world in philosophy?

The actual world, then, as the limit of a series of increasingly more inclusive situations in this sense, is simply the entire physical universe: all the things that are some spatiotemporal distance from the objects in some arbitrary initial situation, structured as they in fact are; and other possible worlds are …

## What is modal logic with example?

Even in modal logic, one may wish to restrict the range of possible worlds which are relevant in determining whether ◻A is true at a given world. For example, I might say that it is necessary for me to pay my bills, even though I know full well that there is a possible world where I fail to pay them.

## What is metaphysically possible?

Metaphysical possibility is one way of thinking about the possibility of something being the case, a way that is often of special relevance to philosophers. If you think about it, we often use the phrase ‘x is possible’ in a variety of ways.

## What are the different types of modality?

Modality is generally related to the necessity, possibility, obligation, permissibility, feasibility and certainty etc. As for the classification of modality, there are several proposals. However, many scholars agree that there are generally two major types: epistemic modality and deontic modality.

## What are the 3 types of modality?

The 3 Categories

• Modals of Possibility: can, could, may, might.
• Modals of Deduction: could, may, must.
• Modals of Expectation: shall, should (rarely), will, would.

## What are the 12 modals?

The modal verbs are: can, could, may, might, will, would, shall, should, must, ought to, dare and need to.

## How do you explain modality?

Modality is about a speaker’s or a writer’s attitude towards the world. A speaker or writer can express certainty, possibility, willingness, obligation, necessity and ability by using modal words and expressions. Speakers often have different opinions about the same thing. These speakers are looking at the same thing.

## What is another word for modalities?

In this page you can discover 10 synonyms, antonyms, idiomatic expressions, and related words for modality, like: method, mode, paradigm, mood, sensory system, sense modality, multimodality, somatic, perceptual and neurophysiological.

## What are the 4 modalities?

The four widely accepted learning modalities (or modes) are known by the acronym VARK: Visual, Auditory, Reading/Writing, and Kinesthetic. They are sometimes inaccurately referred to as “learning styles” which implies that each learner has a “style” of learning that should be maximized in all learning situations.