This handout introduces conditional statements as we use them in English, and then describes with technical detail how conditional statements work in Classical and Biblical Greek and in Latin, comparing and contrasting along the way. It is meant for reference, as it contains all information on conditional statements in every textbook listed in the bibliography. Sadly some of the formatting has been lost when I put it online, so please write to me at teacher.learnnewtestamentgreek@gmail.com if you would like a PDF of the complete handout, in a more readable format.
1. Conditional Statements in English
Here is an example of a conditional statement:
‘If he drinks too much then he will fall over.’
Conditional statements have two parts: the ‘protasis’ puts forward a circumstance, which might result in an ‘apodosis’ being given back in consequence. Above the protasis is ‘If he drinks too much,’ and the apodosis is ‘then he will fall over.’ They can be written in either order, so we could say, ‘He will fall over if he drinks too much.’
There are six possible types of conditional statements:
| Future Open (fulfilled/fulfillable, real) | Future Closed (unfulfilled, unreal) |
| Present Open (fulfilled, real) | Present Closed (unfulfilled, unreal) |
| Past Open (fulfilled, real) | Past Closed (unfulfilled, unreal) |
Grammarians variously refer to these statements as either ‘open/closed,’ ‘fulfilled/unfulfilled’ or ‘real/unreal,’ depending on which tense is being referred to and which grammarian is writing; we will refer to them all as ‘open’ or ‘closed’ here, until we get to Latin, which makes more sense as ‘real/unreal.’
An ‘open’ conditional statement has a protasis that yet may or may not be the case. The example given above is a future open conditional, because we do not yet know how much I will drink.
A ‘closed’ conditional statement refers to one that we already know or strongly suspect not to be the case (it is closed off from possibility). So, a present closed conditional might be said if onlookers watched someone standing up and drinking, and one of them said, ‘If he were drinking too much then he would be falling over.’ Both the protasis and apodosis refer to what is happening in the present, but the apodosis refers to what is closed off from possibility by the fact that they can see he is still standing.
Let’s have the same table as above again, but this time with examples:
| If he drinks too much then he will fall over | If he did drink too much then he would indeed fall over; but he plans to drink in moderation. |
| If he is drinking too much then he is falling over. | If he were drinking too much then he would be falling over. |
| If he drank too much then he was falling over. | If he had drunk too much then he would have been falling over; but he was standing. |
These are the six different types of conditional statements: open or closed statements, in each of the three tenses. Each of these six examples contains a protasis and an apodosis, which together form either an open or closed statement. It is not usually possible for a protasis to be open while an apodosis is closed, because ‘open’ and ‘closed’ describe the statement as a whole (but Latin does occasionally mix them).
However, it is easy to mix tenses, particularly between past and present. So, one could have an open conditional statement in which the protasis is past and the apodosis is present: ‘If he drank too much [past] he must be falling over now [present].’ This is an open conditional statement, because it leaves open the possibility that he is drinking too much. It has not been closed off from possibility, because we do not know how much he is drank. However, it mixes past and present: the protasis is past, but the apodosis is present. One could make the protasis past and the apodosis future: ‘If he drank too much then he will fall over.’ Or, with a bit of imagination, one could make the protasis present and the apodosis past: ‘If he is drinking too much, bad things must have happened last night.’ Was this an open or closed conditional?
In sum:
- A conditional statement expresses cause and effect with a protasis (cause) and an apodosis (effect).
- The whole conditional statement, including both protasis and apodosis, is either open or closed (aside from some cases in Latin). Open conditional statements tell us a cause and effect that are open to possibility, because we do not yet know whether this cause and effect have actually happened, are happening or will happen. Closed conditional statements tell us something that we are sure did not happen, is not happening, or will not happen – and tell us what would have resulted if they had happened.
- Open and closed conditional statements can be either past, present or future, or have one tense in the protasis and another in the apodosis.
Finally, let’s see the same table again, but this time with fuller grammatical definitions:
| Open | Closed | |
| Future | If the protasis is to be true then the apodosis will follow. If X happens then Y will happen. X->Y (both future) | A protasis that we strongly expect will not happen would have led to an apodosis. X would lead to Y but neither are expected to happen. |
| Present | If the protasis is true then the apodosis follows. If X is happening then Y is happening. X->Y (both present) | A protasis that is not true would be leading to an apodosis. If X were happening then Y would be happening. |
| Past | If the protasis was true then the apodosis followed. If X happened then Y happened. X->Y (both past) | If a protasis had been true then an apodosis would have followed. If X had happened then Y would have happened. |
Types of conditional statement (open or closed) may not normally be mixed. However, tenses may. One could thus say that writing conditional statements is a pick’n’mix in which one must either keep left or keep right (except in Latin where it is possible to mix open and closed, though still quite rare).
Latin and Greek have different rules about how to write conditional statements, but for both languages there are set ways one writes the protasis and apodosis depending upon the tense of the clause and whether it is in an open or closed conditional statement. Also, the above is a good starting point for Greek, but things change a bit with Latin. Let us being with Classical Greek.
2. Classical Greek conditional statements operate according to the following formulas:
| OPEN | OPEN | CLOSED | CLOSED | |
| Protasis | Apodosis | Protasis | Apodosis | |
| Future | εἄν + subjunctive | Future indicative | εἰ + optative | Optative + ἄν |
| Present | εἰ + present indicative | Present indicative | εἰ + imperfect indicative | Imperfect indicative + ἄν |
| Past | εἰ + past indicative | Past indicative | εἰ + aorist indicative | Aorist indicative + ἄν |
- Sometimes the future open conditional is also written with εἰ + future indicative for the protasis, like with present and past open conditionals. This is particularly the case if the unavoidable nature of the apodosis is being stressed, like in threats or warnings. Similarly, since the Latin future open conditional is only written with the indicative, it is only used for this sense of a stressed threat or warning.
- Greek open conditionals carry no implication regarding whether the apodosis is fulfilled or not, but merely indicate that it is open to possibility. In Greek, certainty is on the side of closed conditionals, which are certainly unfulfilled (so future conditionals are usually open, because the future is uncertain). This is different from Latin, where certainty is on the side of open conditionals (they describe definite consequences of possible actions), so future conditionals tend to be closed, where the implication is that they exist merely in theory. In sum: Greek open conditionals are possibly open, but closed conditionals are certainly closed. Latin open/real conditionals express certain results if that protasis occurs, but closed/unreal conditionals express things that likely would have been the case.
- In Greek conditionals μή is used for negative protases and οὐ for negative apodoses (compare Latin nisi and non).
- εἄν + subjunctive can also be used for an indefinite present, ‘if ever you should…,’ which is a common occurrence in Koine/New Testament Greek.
- Greek past closed conditionals could use the imperfect rather than aorist to express a repeated or specifically continual action.
- Since there is no aorist indicative of εἰμί, the imperfect must be used in all past-tense conditionals.
- Greek protases can be replaced by participle phrases or genitive absolutes, which would still be negatived by μή.
- Since it is only the presence of ἄν in the apodosis that marks the conditional as closed, one cannot begin to translate the protasis before reading the apodosis.
- The apodosis can be an imperative: ‘If this happens, then do that!’
- Though the above are by far the most common types of conditional statement, there are a few more possible ones. See p. 562 of The Cambridge Grammar of Classical Greek (Cambridge: Cambridge UP, 2019) for a table summarising pp. 550-561, which describes all of these in full. However, the above table includes all that is taught in Reading Greek: Grammar and Exercises (Cambridge: Cambridge UP, 2007) (summarised on p. 460) and John Taylor, Greek Beyond GCSE (London: Bloomsbury, 2017), pp. 22-29, compared with Latin on p. 332.
3. New Testament Greek conditional statements operate according to the following formulas:
| OPEN | OPEN | CLOSED | CLOSED | |
| Protasis | Apodosis | Protasis | Apodosis | |
| Future | εἄν + subjunctive | Future indicative | No complete examples – some partial. | |
| Present | εἰ + present indicative | Present indicative | εἰ + imperfect indicative | Imperfect indicative + ἄν |
| Past | εἰ + past indicative | Past indicative | εἰ + aorist indicative | Aorist indicative + ἄν |
- This table is mostly unchanged from Classical Greek, except that there are very few examples of closed future conditionals (see below).
- There are some partial future closed conditionals in the New Testament. They either mix optative and subjunctive, omit the protasis, omit the apodosis or contain a verbless apodosis.
- As in Classical Greek, the protasis can be a participle clause or genitive absolute, but this can also be the case even if the participle is substantival, such as in the Beatitudes.
- Not just the apodosis but also the protasis can be an imperative, such as in John 2:19.
- Though usually used with a future apodosis, the future open conditional is actually used to express any condition that is of uncertain but still likely fulfilment, as opposed to the closed future for uncertain but unlikely fulfilment (as stated above, such statements did exist already in Classical Greek). In New Testament Greek the apodosis can be in any tense for these conditionals. With the subjunctive in Koine taking over from the optative in Classical, the future open conditional had to take over for any condition that expresses something hypothetical and unlikely to occur, or hypothetical and will not occur. It is also used for general principles, often with a present apodosis. See John 11:9 for an example, and Daniel B. Wallace, Greek Grammar: Beyond the Basics (Grand Rapids: Zondervan, 1996), pp. 696-699 for more information.
4. Latin conditional statements operate according to the following formulas:
| REAL | REAL | UNREAL | UNREAL | |
| Protasis | Apodosis | Protasis | Apodosis | |
| Future | Si + future indicative | Future indicative | Si + present subjunctive | Present subjunctive |
| Present | Si + present indicative | Present indicative | Si + imperfect subjunctive | Imperfect subjunctive |
| Past | Si + past indicative | Past indicative | Si + pluperfect subjunctive | Pluperfect subjunctive |
- In Latin it makes more sense to speak of ‘real’ and ‘unreal’ conditionals. ‘Real’ conditionals use the indicative and refer to things that are the case or that are strongly expected to be the case. ‘Unreal’ conditionals speak of things that exist only theoretically/subjunctively. For past and present unreal/closed conditionals this works out to mean the same thing as in Greek: the apodosis is unreal because it is closed off from possibility, being only theoretical.
- However, in Latin, future conditionals are normally subjunctive/unreal unless expressing a particular confidence or vividness in the future. Closed conditionals in Greek are conditionals that we are sure have been closed off from possibility; since we are sure of it, it is more difficult to have this type of conditional in the future tense. However, unreal conditionals in Latin are conditionals that only exist in theory but not in reality; since we are unsure of them it is easier to have this type of conditional in the future tense. Putting this again even more precisely: the right columns in Greek expresses conditionals that we are sure are not the case, but the right columns in Latin expresses things that we are theorising would be the case. This difference between certain that not and uncertain if yes is why future conditionals are more naturally open (on the left) in Greek but more naturally unreal (on the right) in Latin. In both languages this causes the other, rarer, form to take special meaning: the rarer Greek future closed is used to express a conditional that could take place but we confidently expect it not to. The rarer Latin future real is used if the unavoidable nature of the apodosis is being stressed, like in threats or warnings. One could also describe this as being more ‘vivid.’ In both instances the rarer form is the one where we express the type of conditional which in that language expresses most certainty with the inherently uncertain future.
- One effect of this is that the Latin unreal future conditional equates in meaning to the Greek open future conditional, since they are both the default way of doing straightforward conditionals in the future, in which ever form is less certain in that language. But since Greek places ‘openness’ (the unknown) on the left of the table, that is how it expresses future conditionals, and since Latin places ‘theoreticality’ (the unknown) on the right of the table, that is how it expresses future conditionals.
- A negative protasis is instead introduced by nisi. If the apodosis is negative it uses non.
- Also note that Latin can in fact sometimes mix real and unreal conditionals, using the indicative in one clause and the subjunctive in the other. More commonly, and like Greek, it can mix tenses.
5. Bibliography
De Bakker, Mathieu, Luuk Huitink, Evert van Emde Boas and Albert Rijksbaron, The Cambridge Grammar of Classical Greek (Cambridge: Cambridge UP, 2019)
Balfour, Glenn M., A Step-by-Step Introduction to New Testament Greek (Mattersey: Mattersey Hall, 2005)
Cullen, Henry and John Taylor, Latin to GCSE 2 (London: Bloomsbury, 2016)
Jones, Peter and Keith Sidwell, Reading Greek: Grammar and Exercises (Cambridge: Cambridge UP, 2007)
Taylor, John, Greek Beyond GCSE (London: Bloomsbury, 2017)
Wallace, Daniel B., Greek Grammar: Beyond the Basics (Grand Rapids: Zondervan, 1996)
Wheelock, Frederic M., Richard A. LaFleur (ed.), Wheelock’s Latin: 6th Edition Revised (New York: HarperCollins, 2005)
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