Capacity to buy and sell is regulated by the general law concerning capacity to contract, and to transfer and acquire property: Provided that where necessaries are sold and delivered to an infant or minor, or to a person who by reason of mental incapacity or drunkenness in incompetent to contract, he must pay a reasonable price therefor.

}Necessaries~ in this section mean goods suitable to the condition in life of such infant or minor or other person, and to his actual requirements at the time of the sale and delivery.