Step Up, Step Back. When Should We Do Each?
When does it make sense to be careful with how much we speak?

(יז) שִׁמְעוֹן בְּנוֹ אוֹמֵר, כָּל יָמַי גָּדַלְתִּי בֵין הַחֲכָמִים, וְלֹא מָצָאתִי לַגּוּף טוֹב אֶלָּא שְׁתִיקָה. וְלֹא הַמִּדְרָשׁ הוּא הָעִקָּר, אֶלָּא הַמַּעֲשֶׂה. וְכָל הַמַּרְבֶּה דְבָרִים, מֵבִיא חֵטְא:

(17) Shimon, his son, says: All my days I grew up among the Sages, and I did not find anything better for the body than silence. And the interpretation of Torah should not be the focus, but rather the actions inspired by the Torah. And whoever increases words brings sin.

(טו) שַׁמַּאי אוֹמֵר, עֲשֵׂה תוֹרָתְךָ קְבַע. אֱמֹר מְעַט וַעֲשֵׂה הַרְבֵּה, וֶהֱוֵי מְקַבֵּל אֶת כָּל הָאָדָם בְּסֵבֶר פָּנִים יָפוֹת:

(15) Shammai says: Make your Torah study fixed, say little and do much, and receive every person with a pleasant expression.

1) Why do the Rabbis in Pirkei Avot think that it is wise to limit speech?

2) What are the downsides of talking too much?

When are we obligated to speak up?

מסחת שבת

כל מי שאפשר למחות לאנשי ביתו ולא מיחה - נתפס על אנשי ביתו, באנשי עירו - נתפס על אנשי עירו, בכל העולם כולו - נתפס על כל העולם כולו. אמר רב פפא: והני דבי ריש גלותא נתפסו על כולי עלמא. כי הא דאמר רבי חנינא: מאי דכתיב (ישעיהו ג) ה' במשפט יבא עם זקני עמו ושריו, אם שרים חטאו -זקנים מה חטאו? אלא, אימא: על זקנים שלא מיחו בשרים.

Masechet Shabbat 54b-55a

Anyone who is able to protest against the transgressions of one's household and does not, is punished for the actions of the members of the household.

Anyone who is able to protest against the transgressions of one's townspeople and does not, is punished for the transgressions of the townspeople.

Anyone who is able to protest against the transgressions of the entire world and does not is punished for the transgressions of the entire world.

Questions

1) Is it fair to be held responsible for not stopping someone else from doing something wrong?

2) How do our responsibilities to speak up differ when someone is doing something wrong in our home from when someone is doing something wrong on the other side of the world?