Allen and Greenough's New Latin Grammar for Schools and Colleges
J. B. Greenough, G. L. Kittredge, A. A. Howard, Benj. L. D'Ooge, Ed.

1. “sī tū exercitusque valētis, bene est ” (Fam. 5.2) , if you and the army are well, it is well. [Present Condition.]
2. “haec igitur, sī Rōmae es; sīn ades, aut etiam sī ades, haec negōtia sīc sē habent ” (Att. 5.18) , this, then, if you are at Rome; but if you are away—or even if you are there—these matters are as follows. [Present Condition.]
sī Caesarem probātis, in mē offenditis (B. C. 2.32.10), if you favor Cæsar, you find fault with me. [Present Condition.]
3. “sī quī māgnīs in eō genere exstitērunt, nōn satis Graecōrum glōriae respondērunt ” (Tusc. 1.3) , if any have shown themselves of great genius in that department, they have failed to compete with the glory of the Greeks. [Past General Condition, not distinguished in form from Particular.]
4. “accēpī Rōmā sine epistulā tuā fasciculum litterārum in quō, sī modo valuistī et Rōmae fuistī, Philotīmī dūcō esse culpam nōn tuam ” (Att. 5.17) , I have received from Rome a bundle of letters without any from you, which, provided you have been well and at Rome, I take to be the fault of Philotimus, not yours. [Mixed: Past condition and Present conclusion.]
5. quās litterās, sī Rōmae es, vidēbis putēsne reddendās (id. 5.18), as to this letter, if you are at Rome, you will see whether in your opinion it ought to be delivered. [Mixed: Present and Future.]
6. “sī nēmō impetrāvit, adroganter rogō ” (Lig. 30) , if no one has succeeded in obtaining it, my request is presumptuous. [Past and Present.]

[*] a. In these conditions the apodosis need not always be in the Indicative, but may assume any form, according to the sense:—

1. “sī placet ... videāmus ” (Cat. M. 15) , if you please, let us see. [Hortatory Subjunctive, § 439.]
2. “sī nōndum satis cernitis, recordāminī ” (Mil. 61) , if you do not yet see clearly, recollect. [Imperative.]
3. “sī quid habēs certius, velim scīre ” (Att. 4.10) , if you have any trustworthy information, I should like to know it. [Subjunctive of Modesty, § 447. 1.]

[*] Note.--Although the form of these conditions does not imply anything as to the truth of the supposition, the sense or the context may of course have some such implication:—

1. “nōlīte, sī in nostrō omnium flētū nūllam lacrimam aspexistis Milōnis, hōc minus ei parcere ” (Mil. 92) , do not, if amid the weeping of us all you have seen no tear [in the eyes] of Milo, spare him the less for that.
2. “petimus ā vōbīs, iūdicēs, sī qua dīvīna in tantīs ingeniīs commendātiō dēbet esse, ut eum in vestram accipiātis fidem ” (Arch. 31) , we ask you, judges, if there ought to be anything in such genius to recommend it to us as by a recommendation of the gods, that you receive him under your protection.

In these two passages, the protasis really expresses cause: but the cause is put by the speaker in the form of a non-committal condition. His hearers are to draw the inference for themselves. In this way the desired impression is made on their minds more effectively than if an outspoken causal clause had been used.

Future Conditions