or want of consideration, so merely
gratuitous services, as voluntarily assisting to save property from
fire, or securing beasts found straying, or paying another's debts
without request, afford no consideration upon which payment for their
value can be lawfully claimed; there being no promise of compensation.
But if a person knowingly permits another to do certain work, as plowing
his field, or hoeing his corn, although the work may have been commenced
without his order or request, his consent will be regarded in law as an
_implied promise_ to pay for the value of the labor, unless the
circumstances of the case are such as to forbid the presumption.

Sec.10. A consideration must also be _possible_, and in accordance with
law, sound policy, and good morals. A contract founded upon an
impossible consideration is void. No man can be lawfully bound to do
what is not in the power of man to do. But it is otherwise, if the thing
to be done is only at the time impossible in fact, but not impossible in
its nature. Hence, inability from sickness to fulfill an agreement, or
the impossibility of procuring an article of a certain kind or quality
which a person has agreed to deliver, would not exempt him from
liability in damages for the non-performance of his contract.

Sec.11. A contract, the consideration of which is _illegal_ or _immoral_,
may be avoided by either party. A man can not be held to an agreement to
do acts forbidden by the law of God or by the laws of the state. But if
an illegal contract has been executed; in other words, if the wrong has
been done, the party in the wrong can not renounce the contract; for the
general rule is, that no man can take advantage of his own wrong; and
the innocent party alone has the privilege of avoiding the contract. If
both parties are guilty, neither can, in ordinary cases, obtain relief
on a contract that has been executed.

Sec.12. The rule that a consideration is necessary to a valid contract
applies to all contracts and engagements not under seal, except bills of
exchange and negotiable notes after they have passed into the hands of
an innocent indorsee. (See Promissory Notes.) In contracts under seal, a
consideration is necessarily _implied_ in the solemnity of the
instrument.

Sec.13. It is declared by the English statute of frauds, which prevails
generally in the United States, that an agreement which is not to be
performed within one year from the time of making it, shall