Source: http://dcc.dickinson.edu/grammar/latin/purpose-clauses
Timestamp: 2019-04-18 10:30:18+00:00

Document:
529. The subjunctive in the clause of purpose is hortatory in origin, coming through a kind of indirect discourse construction (for which see § 592). Thus, mīsit lēgātōs quī dīcerent means he sent ambassadors who should say, i.e. who were directed to say; in the direct orders the verb would be dīcite, which would become dīcant in the indirect discourse of narrative (§ 588) or dīcerent in the past (cf. hortatory subjunctive in past tenses, § 439.b). The subjunctive with ut and nē is, in general, similar in origin.
530. A clause expressing purpose is called a Final Clause.
531. Final Clauses take the subjunctive introduced by ut (utī), negative nē (ut nē), or by a relative pronoun or adverb.
Pure clauses of purpose, with ut (utī) or nē (ut nē), express the purpose of the main verb in the form of a modifying clause.
They brought Cincinnatus from the plough that he might be dictator.
They halt in order to support their own men.
He barricaded the gates, in order that the soldiers might not break into the town.
He orders scaling ladders to be got ready, in order not to let slip any opportunity.
Note 1— Sometimes the conjunction has a correlative (ideō, idcircō, eō cōnsiliō, etc.) in the main clause (cf. § 56.a).
For this reason we are subject to the laws, that we may be free.
He led the troops across with this design—to storm the fort.
Note 2— Ut nōn sometimes occurs in clauses of purpose when nōn belongs to some particular word.
Relative clauses of purpose are introduced by the relative pronoun quī or a relative adverb (ubi, unde, quō, etc.). The antecedent is expressed or implied in the main clause.
Lucius Decidius Saxa is sent to examine the ground (who should examine, etc.).
He wrote speeches for other men to deliver.
that when he was dead there would be nobody from whom I could learn.
You have left him no ground even to make a stand against you.
Note— In this construction quī = ut is (etc.), ubi = ut ibi, and so on (§ 537.2).
a. The ablative quō ( = ut eō) is used as a conjunction in final clauses which contain a comparative.
He took advantage of liberty, that he might bluster with more impunity.
Note— Occasionally quō introduces a final clause that does not contain a comparative.
Lucius Sulla had treated the army luxuriously, in order to make it devoted to him.
For quōminus ( = ut eō minus) after verbs of hindering, see § 558.b.
532. The principal clause, on which a final clause depends, is often to be supplied from the context.
and, not to be tedious, we ordered, etc.
But, to return to the same point, this was the cause of fear.
It was the act of one rash enough, not to say daring.
Note 1— By a similar ellipsis the subjunctive is used with nēdum, sometimes nē (still less, not to mention that).
Far more will they hunt up at once some sort of crime and scandal.
Still less is it easy at sea and on a journey.
For prosperity overmasters the soul even of the wise; much less did they with their corrupt morals put any check on victory.
Note 2— With nēdum the verb itself is often omitted.
aptius hūmānitātī tuae quam tōta Peloponnēsus, nēdum Patrae (Fam. 7.28.1)fitter for your refinement than all Peloponnesus, to say nothing of Patræ.
For Substantive Clauses involving Purpose, see §§ 563 - 566.
a. The usual way of expressing purpose is by ut (negative nē), unless the purpose is closely connected with some one word, in which case a relative is more common.
They send envoys to Dumnorix, in order through his intercession to obtain (this favor) from the Sequani.
He sent the soldiers to follow up those who had fled.
Curio sends forward cavalry to withstand the first attack.
d. The future participle used to express purpose is a late construction of inferior authority (§ 499.2).
For the poetical Infinitive of Purpose, see § 460.c. For the present participle in a sense approaching that of purpose, see § 490.3.

References: § 592
 § 439
 § 56
 § 558
 § 460
 § 490