Truthmaker theory is "the branch of metaphysics that explores the relationships between what is true and what exists".
Various representational entities, like beliefs, thoughts or assertions can act as truthbearers.
Truthmaker theory has been applied to various fields in metaphysics, often with the goal of exposing ontological cheaters: theorists who are committed to certain beliefs but do not or cannot account for the existence of a truthmaker for these beliefs.
This maximalist position leads to philosophical difficulties, such as the question of what the truthmaker for an ethical, modal or mathematical truthbearer could be.
Those who find the Parmenidean insight sufficiently compelling often take it to be a particularly enlightening metaphysical pursuit to search for truthmakers of these kinds of propositions.
While the existence of truthmakers may seem an abstruse question, concrete instances are at the heart of a number of philosophical issues.
[5] Alternatively, a divine command metaethicist may insist that the only possible candidate for a truthmaker of a moral claim is a command from a perfect God, and hence if moral claims are true and a truthmaker theory holds, then God exists.
In propositional calculus molecular sentences are composed through truth-functional logical connectives.
[1][6] They aim to make our intuitions about the role and nature of truthmaking explicit.
[7] Or in the words of Thomas Aquinas: "A judgment is said to be true when it conforms to the external reality".
For one, correspondence theory aims to give a substantive account or a definition of what truth is.
Truthmaker theory, on the other hand, has the goal of determining how truth depends on being.
[17] Arguments based on truthmaker theory have been used in various fields to criticize so-called "ontological cheaters".
If such a belief was true then its truth would be brute or free-floating: it would be disconnected from any underlying reality.
This is opposed to the basic intuition behind truthmaker theory that truth depends on being.
[18] Defense strategies open to theorists accused of ontological cheating include denying that the proposition in question is true, denying the legitimacy of truthmaker theory as a whole or finding a so-called "proxy" or "trace" within their preferred ontology.
It holds that past, present and future existents are equally real.
He claimed that we can account for unperceived objects in terms of counterfactual conditionals: It is true that the valuables are in the safe because if someone looked inside then this person would have a corresponding sensory impression.
Actualists face the problem of how to account for the truthmakers of modal truths, like "it was possible for the Cuban Missile Crisis to escalate into a full-scale nuclear war", "there could have been purple cows" or "it is necessary that all cows are animals".
[25][26] A well-known account relies on the notion of possible worlds, conceived as actual abstract objects, for example as maximal consistent sets of propositions or of states of affairs.
This account relies heavily on a logical notion of modality, since possibility and necessity are defined in terms of consistency.
An alternative solution to the problem of truthmakers for modal truths is based on the notion of "essence".