Those who talk too much do little else. If you talk more than you listen, you not only deprive yourself of many opportunities to accumulate useful knowledge, but you also disclose your plans and purposes to people who will take great delight in defeating you, because they envy you.
Remember, also, that every time you open your mouth in the presence of a person who has an abundance of knowledge, you display to that person, your exact stock of knowledge, or your lack of it! Genuine wisdom is usually conspicuous through modesty and silence.
~ Napoleon Hill, Think & Grow Rich (1937)