Rashi's unusual phrasing of the four sons

Question

At the end of Parashat Bo (Exodus 13:14), Rashi enumerates the Four Sons of the Passover Seder:

דברה תורה כנגד ארבעה בנים, רשע ושאינו יודע לשאול והשואל דרך סתומה והשואל דרך חכמה

The Torah spoke regarding four sons: the wicked one (Exod. 12:26), the one who does not understand to ask (Exod. 13:8), the one who asks [a] general [question], and the one who asks in a wise manner. — [from Yerushalmi, Pes. 10:4]

(Emphases mine. References inserted by chabad.org.)

We (like the Yerushalmi Rashi apparently draws from) refer to the wise son simply as "wise son." Why does Rashi refer to him as "the one who asks in a wise manner"?

Answer 1

My instinct, having done no research on the topic, suggests that Rash"i is in fact softening both ends of the descriptive spectrum to make the point that "there are no X people, just X questions".

Note that the wise son is not the only one whose designation shifts between the text of the Y'rushalmi to Rash"i's expression of it. Tipesh (stupid) also becomes sho'el derech s'tuma (asks [a] general [question]).

"תני ר' חייה "כנגד ארבעה בנים דיברה תורה: בן חכם, בן רשע, בן טיפש, בן שאינו יודע לשאול

With the exception of the wicked son, whose motivation in initiating the dialogue is assumed to be misfounded due to his religious or philosophical shortcomings, the sons could each be the personification of a mode of questioning rather than a human typology. Similarly, the response to each of them is a response to the approach he is taking rather than a wholesale reaction to what he represents. (Again, the wicked one is the exception to this rule.)

It therefore would follow logically that they are categorized by the interrogative stance they demonstrate (Rash"i's version) and not the their underlying inferred intellectual personalities (Y'rushalmi's version).

Answer 2

I'm sure it's addressed in the supercommentaries, but first guess: Rashi's choice of language highlights the form of the question:

The one who doesn't ask, well, doesn't ask. It's just "and tell this to your child."

The wicked one, it's (Ex. 12:26): וְהָיָה, כִּי-יֹאמְרוּ אֲלֵיכֶם בְּנֵיכֶם: מָה הָעֲבֹדָה הַזֹּאת, לָכֶם "when your children tell you" (not "ask you").

Only the remaining two sons actually "ask" (שאל) as such in the text:

The son who asks simply (Ex. 13:14): וְהָיָה כִּי-יִשְׁאָלְךָ בִנְךָ, מָחָר--לֵאמֹר מַה-זֹּאת
And the one who asks wisely (Deut. 6:20): כִּי-יִשְׁאָלְךָ בִנְךָ מָחָר, לֵאמֹר: מָה הָעֵדֹת, וְהַחֻקִּים וְהַמִּשְׁפָּטִים