Learn to Say “I Don't Know”
Too many people (and one is too many) fear admitting that they don't know something. They fear admitting they're not perfect or on top of everything that they think they should be on top of.
They're afraid to say I don't know.
The problem is that you can't know everything. You're often thrust into new situations at work or into new social circles. You have new ground to tread, new information to assimilate, new ways of doing things to learn, new people to meet.
Those situations are often outside your knowledge or experience. There's no shame, no matter what some people seem to think, in admitting there are gaps in your knowledge.
If you want to grow and to learn, you need to swallow your pride and say I don't know. Say it loudly. Say it clearly. Say it proudly.
To get past your hesitancy, you need to ask yourself What's the worst that can happen? Will someone laugh at you? Will they look down upon you? Will they think you're an ignorant lout? If they do, so what? The problem lies with them, not you.
The positives of saying I don't know outweigh the negatives. If you say I don't know, you'll learn something. You'll grow. That's a great payoff for saying three simple words.