Final answer:
A person with intervals of insanity or delusions can enter into a binding contract if they are in a lucid interval and can fully understand the transaction when making the contract. However, if they are not in a lucid state at the time of the agreement, the contract may be void or voidable.
Step-by-step explanation:
The question asks whether a person who has not been judicially declared insane but experiences intervals of insanity or delusions can make a binding contract. Under general contract law, a contract is not binding if one party lacks the capacity to enter into a contract. Capacity can refer to several different aspects, such as age, mental soundness, and sobriety. For a person who has intervals of insanity or delusions, they must have the ability to understand the nature and consequences of the transaction at the time the contract is made. If they are in a lucid interval and can comprehend the contract's terms and ramifications, then generally, the contract can be considered binding. However, if they are suffering from insanity or delusions at the time of making the contract, it may be declared void or voidable, depending on the severity and impact of their mental condition on their decision-making abilities.
It is important to recognize that the determination of legality and binding nature of such contracts can vary significantly between jurisdictions, and local laws and cases may offer specific rulings that would apply.