Bdtyk

I have heard the claim that a claim must be explicit by definition, but do not see any definition that supports this.

An example of how "implicit claim" is used from this Wikipedia page on Fear,_uncertainty_and_doubt.

All three implicit claims have been disputed, and some of their
elements disproven, by environmental groups, consumer-protection
groups, and the industry self-regulatory Better Business Bureau

I would have thoughts claims can be implicit, either in the case of a point assumed for an argument without being stated directly or a point being made that leads most people to the same conclusion without stating it directly.

Essentially I had thought any claim made that is not stated directly but implied would be an implicit claim. Is this incorrect?

In English can claims be implicit, or can they only be explicit?

According to this paper, both explicit and implicit claims exist:

We argue that in selling a product or service or purchasing inputs,
companies issue both explicit and implicit claims. The former refers
to the contractual basis on which goods and services are sold or
purchased by companies whereas the latter relates to company promises
to stakeholders (employees, customers, suppliers, etc.) that are
either too vague or too costly to specify in writing.

The paper is in the area of corporate reputation, but the concept of claims that are stated and claims that are implied holds for other subjects as well.

There is a difference between an implicit claim and an assumption. An assumption is an unstated point that must be true for an argument or chain of reasoning to work. One makes an assumption. An implicit claim is something that is claimed within a claim. The person doesn't assume the implicit claim is true, he implicitly claims it is true.

For example: "Despite his low popularity, Newt Gingritch may yet take the Republican nomination." Here there is an implicit claim that Newt Gingritch has low popularity. We are in fact claiming it, but we're doing it in an indirect way that tries to disguise the fact that we're claiming it.

Thanks to John Lawler's recent contributions here on ELU, I think I can say what we're dealing with here is implicature (things non-explicitly conveyed by an utterance), and Grice's cancellability test (if anything in the implicature isn't true, the utterance is linguistically flawed).

As regards the specific word claim, the fact is that increasingly over the past half-century and more we see written instances where it's preceded by implicit or explicit, so I think it's reasonable to say that neither of those adjectives are inherently included or precluded by the word itself.

All that matters is that the audience should understand that a (potentially contestable) assertion is being made. You can't "claim that water is wet", for example, because that's not even contestable in principle. Stretching things to the limit though, there are 3380 written instances of "claim the moon is made of green cheese" in Google Books. Which are linguistically valid, imho, since at least the claim can be contested.

There is no need for a definition, a claim is intrinsically explicit, other wise how could it be a claim?

On the other hand in law, one could claim a house as belonging to him, but the contents are not implicitly assumed to be his.

An implicit claim is one that is implied by other statements or claims.

For example, if you have been found guilty of a federal crime in the US and I say "I can get you pardoned for that " then I am implicitly claiming to have influence with the US President. I haven't actually stated it but since the President is the only one who can grant such a pardon anyone can reasonably deduce I mean it. I could later say "I never said I had influence with the President", and that would be true, but I made the implicit claim.

Claims can definitely be implicit according to both logic and the English language.