This quote means that if you do not listen to others, you will be unable to fully understand what they are saying and will ultimately be unable to learn from their words. In other words, if you do not listen to others, you will become "deaf" to their wisdom and insights. This phrase can be interpreted as a warning to pay attention to others and listen carefully in order to avoid missing out on valuable information. It can also be seen as a reminder to be open to hearing and considering different perspectives, as this can help us to better understand the world around us and make more informed decisions.