Answering "I don't know" (hereby referred to as IDK) is not an indication of ignorance. On the contrary, it may indicate that you're not willing to make wrong assumptions or provide inaccurate information. I think we've been educated in believing that whatever question we've been asked, we must answer. This is probably true in a traditional school environment, where students are expected to show successful memorization of notions. In those cases "I don't know" means "I wasn't listening to the lesson" or "I didn't study". There are other contexts though, where IDK not only is the most accurate answer, but it's probably the more useful. Imagine you're having a surgery operation, but you can hear what surgeons say. One is a doctor fresh from university, at his first operation. He/she will perform the operation. The expert surgeon asks a question before the rookie can proceed. There's probably 'the ri...