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What can bind a party to a contract other than executing it by signing it by hand or electronically and delivering it? My question is only about this element in making a contract, not consideration or other elements. The other topic cited mentions that signing per se is not required, but something is, and therein is my question.
I'm thinking of a situation in which person A imposes a burden on person B and person B wants to be paid for fulfilling that burden, but person A would decline to sign a contract, claims the burden is mandatory when it's not, and might worsen the burden if asked, so isn't asked to.
Example: If someone visits a doctor for an office consultation, gets the consultation, and leaves and then the doctor sends a bill to the visitor, the fact that neither one ever discussed a contract or a price and that the office had no price posted would be irrelevant and a court would rule that the visitor owed. Maybe that's the case only for medicine and some other professions and not for, say, home party hosts, although I think that could be answered by establishing, somehow, that the service provider's service is commercially valuable and deserving of compensation even if the provider is not classified as a professional.
In one case, a jury was persuaded by a photo of a handshake. The parties were major companies, one well known and the other able to build or buy a factory for a big contract. I've also run into people who try not to sign anything due to a religious reason (I think), but they doubtless enter into contracts and execute them somehow, but I don't know how.
Hypothetical case: In the U.S., a person writes a letter to a carpenter known to make a living as a carpenter. (Any occupation will do for this purpose, especially one for which compensation is not always expected, such as house-cleaning.) Both are adult individuals. In the letter, the person asks the carpenter to make a chair. Assume nothing else is in the letter. The carpenter makes the chair and delivers it. The carpenter bills the person for the service. The person says there was no intention to make a purchase, just a thought that the carpenter would like to practice making a chair and seeing someone gladly sit in it. The person has sat in it, is glad for the experience, and happily accepts the chair as a gift. The carpenter never said anything about a gift. Would the person owe?