CRITICAL POST! The 4 major tenses of the derived (D) optative mood of thematic verbs in Mycenaean Linear B:

Here is the paradigm of the 4 major tenses of the optative mood in Mycenaean Linear B, based on the derived (D) template verb, naie (ancient Greek, naiein) = to dwell in, inhabit:

paradigm-of-the-optative-mood-in-linear-b

Note that we have provided two examples of derivative (D) sentences in this table of the paradigms for the 4 tenses of the optative mood in Mycenaean Linear B and ancient Greek in order to facilitate a better understanding of its functionality.

As can be seen from the table above, there are only 4 primary tenses for the optative mood of thematic (and indeed for athematic) verbs in Mycenaean Linear B, as well as in ancient Greek. These are:

the optative present
the optative future
the optative aorist (or simple past)
the optative perfect

There is no optative imperfect. It is a contradiction in terms. How is it possible that something was in fact happening, kept on happening or used to happen, when it is readily apparent that the optative mood always runs contrary to reality. The optative mood only and always refers to potentialities or possibilities, never to actual situations, which of course strictly call for the indicative mood. 

The optative mood has no equivalent whatsoever in any modern Centum or Occidental language, including modern Greek. It lapsed out of use before the advent of modern Greek. The optative mood sometimes plays a similar role to the subjunctive mood in ancient Greek, but by no means always. As a matter of course, we shall not be deriving a table of the tenses of the subjunctive mood in Mycenaean Linear B, for two conclusive reasons:
1. The subjunctive mood occurs nowhere on any Linear B tablets, i.e. it is not attested, or so it would seem so... because...
2. The subjunctive mood is virtually indistinguishable from the active in Mycenaean Linear B, whether or not we are dealing with thematic or athematic verbs, for the simple reason that Mycenaean Linear B cannot distinguish between short and long vowels. In other words, while ancient Greek allows for the subjunctive mood, which calls for the lengthening of the vowel in any person of the present tense, this is impossible in Mycenaean Linear B.

So there would simply be no point in attempting to reconstruct a mood which could not even be observed on Mycenaean Linear B tablets, even it were present. But it never is to be found on any extant tablet, i.e. it is nowhere attested (A), because Mycenaean Linear B tablets almost exclusively deal with inventories, which are by nature factual, thereby automatically calling for the indicative, and precluding the subjunctive.

It may seem counter-intuitive to find the optative on at least one Linear B tablet, but there is a tenable explanation for this phenomenon. Since the tablet in question deals with religious matters, it makes sense for the optative to be present. For instance, it is possible to say in Mycenaean Linear B,

May we all worship the Goddess of the Winds.
-or-
If only they believed in the gods!

These sentences make perfect sense in Mycenaean Greek.

But this still leaves us with the burning question, what on earth is the optative mood?

This is no easy question to answer. But I shall do my level best. To begin with, it is highly expedient to consult the Wikipedia article on the optative mood in ancient Greek:

wikipedia-optative-ancient-greek

since doing so will expedite your understanding of the functions of the optative. Essentially, these are as follows:

1. to express a wish on behalf of the welfare of someone, e.g.:

May you be happy.
May you live long and be prosperous.

2. to express the wish or hope,... if only (which is contrary to reality, as it never happened anyway, no matter how much or how dearly one might have wished it had happened), e.g.:

If only the Mycenaeans had not conquered Knossos.
If only Donald Trump had not won the U.S. Election! (Fat chance of that!)

3. The potential optative expresses something that would or could happen in a hypothetical situation in the future, e.g.

I wouldnt be surprised if the fortress of Mycenae were to fall in the next few years.
I wouldnt be surprised if Donald Trump were impeached. (Good luck for that one!)

4. Potential in the aorist or the past tense, e.g.     

The king of Knossos fled the city for fear that he might be caught and imprisoned.

5. For purpose clauses in past time, the optative can follow the conjunction so that:

The king has brought us all together so that we might discuss the situation regarding the possibility of an outbreak of war.

6. After verbs expressing fear: 

I was afraid that he had gone out of his mind.

7. for formal benedictions or prayers (primarily in the New Testament), e.g.:

May the Grace of the Lord Jesus Christ be with you.
May the Lord grant you mercy.

There are even more uses of the optative, but I do not wish to belabour the point. Suffice it to say, this mood is extremely flexible in ancient Greek. It always references actions or situations contrary to reality. It is often quite difficult for us in this present day and age to really get a grip on the various functionalities of the optative tense in ancient Greek, but get a grip we must if we are ever to really, clearly grasp what ancient Greek sentences relying on the optative actually mean, once we have embarked on that most challenging of journeys, to learn ancient Greek, to easy matter, let me tell you from personal experience.