What are necessaries is determined not simply by the nature of the thing, but by the need of that thing at that time by the particular infant in question. Accordingly if an infant is already supplied either by his guardian or by previous purchases, with sufficient food, clothing, or other necessaries, no further purchase on credit of articles of the same kind can bind him.57 Therefore, whether a minor is living with a parent or guardian who is capable of supplying him with necessaries is a fact vital for determining whether a particular contract made by him is for necessaries. The presumption is that the infant's wants are sufficiently met, and the court will not substitute the judgment of a jury for that of a parent or guardian unless the discretion of the latter has clearly been abused.58 Moreover, if necessaries are furnished an infant when he is living with a parent or guardian the legal inference, in the absence of evidence to the contrary, is that they are furnished, on the credit of the parent or guardian, not of the infant.59
If an infant, when in need, purchases more of the required goods than are essential, recovery can be had by the seller for only so much as were actually needed.60 "It is immaterial whether the plaintiffs did or did not know of the existing supply, just as it is immaterial whether they did or did not know that the defendant was a minor." 61 It has been decided in England 62 that an infant in receipt of an income sufficient to pay for all necessaries nevertheless may bind himself by a purchase on credit; but the contrary has been held in the United States.63 It would seem on principle that though the infant if he had previously wasted the money could buy on credit, otherwise he ought not to be bound, for his power to bind himself should be limited to cases where his protection requires it.64 If it appears that an infant has been sufficiently supplied with money to provide himself with necessaries the burden should be upon the creditor of producing evidence that the money had been previously misapplied.65 So if the infant is living with his parents or guardian, the burden is upon the creditor to prove that the infant was not supplied by them.66 It has been settled that an infant is not bound by his executory promise to buy necessaries,67 but it has not been decided whether in case of a sale where title has passed to the infant but the goods have not been delivered, the infant may repudiate the bargain. It seems reasonable to allow this, if for instance he finds that he no longer needs the goods. Though the elements of contractual liability exist, the unjust enrichment which forms the basis of quasi-contractual liability does not. If this be so the time when the infant becomes bound, if at all, is when the goods are delivered. For this reason in the Uniform Sales Act the moment of delivery is the time considered in determining whether an infant has a previous supply.68
In re Wrexham, M. & C. Q. Ry. Co.,  1 Ch, 440, as illustrating a pos-able undeserved priority.
57 Burghart v. Anger-stein, 6 C. & P, 690; Foster v. Redgrave, L. R. 4 Ex. 35, note; Barnes v. Toye, 13 Q B. D. 410; Johnstone v. Marks, 19 Q. B. D. 509; Conboy v. Howe, 59 Conn. 112, 22 Atl. 35; Pearson v. White, 13 Ga. App. 117, 78 S. E. 864; McKanna v. Merry, 61 111. 177, 180; Trainer v, Trumbull, 141 Mass. 527, 6 N. E. 761; DeoeU v. Lewenthal, 57 Miss. 331, 34 Am. Rep. 449; Perrin v. Wilson, 10 Mo. 451; Nichol v. Steger, 6 Lea, 393.
58 Bainbridge v. Pickering, 2 W. Bl. 1325; Mauldin v. Southern Shorthand University, 126 Ca. 681, 55 S. E. 922; McKanna v. Merry, 61 111. 177; Hoyt v. Casey, 114 Mara. 397,19 Am. Rep. 331; Deoell v. Lewenthal, 57 Miss. 331, 34 Am. Rep. 449; Perrin v. Wilson, 10 Mo. 451; International Text Book Co. v. Connelly, 206 N. Y. 188, 99 N. E. 722, 42 L. R. A. (N. S.) 1115; Guthrie v. Murphy, 4 Watts, 80; Kraker v. Byrum, 13 Rich. L. 163. This principle is said not to be affected by the poverty of the parent or guardian. Hoyt v. Casey, 114 Mass. 397, but this cannot be true in an extreme case. See Trainer v. Trumbull, 141 Mass. 527, 6 N. E. 761.
59Hoyt v. Casey, 114 Mass. 397, 19 Am. Rep. 371.
60 Nicholson v. Willborn, 13 Ga. 467; Johnson v. Lines, 6 Watts & S. 80, 40 Am. Dec. 542.
61 Barnes v. Toye, 13 Q. B. D. 410, 414; Kline v. L'Amoureux, 2 Paige, 419,22 Am. Deo. 652; Nichol v. Steger, 6 Lee, 393.
62Burghart v. Hall, 4 M. & W. 727,
63Brent v. Williams, 79 Miss. 355, 30 So. 713; Rivers v. Gregg, 5 Rich. Eq. 274.
64 Rivers v. Gregg, 5 Rich. Eq. 274.
65 Rivers v. Gregg, 5 Rich. Eq. 274.
See also Nicholson v. Wilborn, 13 Ga. 467.
66 Bainbridge v. Pickering, 2 W. Bl. 1325; Hoyt v. Casey, 114 Mass. 397, 19 Am. Rep. 371; Perrin v. Wilson, 10 Mo. 451; Freeman v. Bridger, 4 Jones L. 1, 67 Am. Dec. 258; Connolly v. Hull, 3 McCord, 6, 15 Am. Dec. 612.
67 See supra, Sec. 240.
68 Sec. 2. The States which have enacted this statute are enumerated infra, Sec. 506.