In Pirkei Avot, Ben Zoma teaches us in Pirkei Avot 4:1 this oft-cited maxim,
בֶּן זוֹמָא אוֹמֵר, אֵיזֶהוּ חָכָם, הַלּוֹמֵד מִכָּל אָדָם, שֶׁנֶּאֱמַר (תהלים קיט) מִכָּל מְלַמְּדַי הִשְׂכַּלְתִּי כִּי עֵדְוֹתֶיךָ שִׂיחָה לִּי
Ben Zoma said:Who is wise? He who learns from every man, as it is said: “From all who taught me have I gained understanding”
However, if one finds himself in Masechet Tamid (32a), he is met with the incident of Alexander the Great - when he approached and asked of the Chachamim for the definition of a Chacham.
אמר להם אידין מתקרי חכים אמרו ליה איזהו חכם הרואה את הנולד
Alexander said to the Elders: Who is truly worthy of being called wise? They said to him, citing a tradition (see Avot 2:9): Who is the wise person? The one who sees and anticipates the consequences of his behavior.
They cited the mishnah found in Pirkei Avot 2:9. The Mishnah there asks for the correct "path" one should take.
אָמַר לָהֶם, צְאוּ וּרְאוּ אֵיזוֹהִי דֶרֶךְ יְשָׁרָה שֶׁיִּדְבַּק בָּהּ הָאָדָם...רַבִּי שִׁמְעוֹן אוֹמֵר, הָרוֹאֶה אֶת הַנּוֹלָד.
He [Rabban Yohanan] said unto them: go forth and observe which is the right way to which a man should cleave?...; Rabbi Shimon said, foresight.
a.) Why did the Chachamim choose the definition from Pirkei Avot 2:9 as opposed to 4:1?
b.) The Mishnah in 2:9 teaches how one should conduct himself - אֵיזוֹהִי דֶרֶךְ יְשָׁרָה שֶׁיִּדְבַּק בָּהּ הָאָדָם, it did not specify what constitutes a Chacham. How did the Chachamim understand it as the latter?
Note: I am aware when I use "definition" for "The definition of a Chacham, it's not it's actual definition, rather a chief characteristic of a Chacham.