Meaning of "may" in "as a scholar may learn..."

I'm analyzing the following phrase:

Or as a scholar may learn some secret language of the ancients, his friends shall say: «Look! he pretends to read this book. But it is unintelligible—it is nonsense.» Yet he delights in the Odyssey, while they read vain and vulgar things.

I'm unsure of the meaning of "may" in this phrase. Looking at the Oxford Dictionary of English online, I'm pretty sure this is not meaning [2] or [3].

Meaning [1] seems strange here. The scholar "may" learn, while his friends "shall say"? What is the value of "may" in this phrase?

This situation is comparable to the subjunctive mood. The word “may” is a mood-setter to create a hypothetical situation. Let's look at your example again:

Or as a scholar may learn some secret language of the ancients, his friends shall say: «Look! he pretends to read this book. But it is unintelligible—it is nonsense.» Yet he delights in the Odyssey, while they read vain and vulgar things.

The word “may” creates the hypothetical situation (of the scholar learning the language), and also sets the reader up for a result of this situation (the friends' dialogue). “May” is simply setting up a hypothetical situation with a result of an action.

This is a special case of definition 1 of Lexico, or 1b of Merriam-Webster.