Summarize this article in one sentence.
So many social errors could be avoided if only more thought were involved. A truly gifted conversationalist will always try to filter what he says before he finally says it. While thinking about everything you're going to say may sound exhausting to some, it doesn't require a lot of brainpower. Really, all you'll usually need is a split-second to figure whether something you say might negatively affect someone around you. If you have a bad feeling about saying something, it's best to keep your mouth shut for the time being. It may help to be conscious of the way your voice is sounding when you speak. While it may be distracting to focus on yourself when you're trying to have a conversation, casually keeping track of the tone, speed and volume of your voice can go a long way towards preventing unintentional rudeness. In particular, be careful with your talking speed. Nervous or awkward people tend to accelerate their speech when they're under pressure. This only serves to add to the awkwardness. There's a lot empathy can do for you in a conversation. Being seen as polite and considerate isn't least among the benefits. Empathy is something virtually everyone has to some extent. The key to bringing it out is to invest a legitimate interest in what the other person is saying. If someone is telling you something about his life, make a concerted effort to see things from his point of view. If he recently lost his job, for example, try to empathize with how that might feel. Empathetic people are in tune with the other person's feelings and it's easier to charm them as such. Empathy works in less-than-pleasant interactions as well. It can be frustrating to talk to someone who is being aggressive or mean-spirited. While it can be easy to let loose on someone like that, you can have an easier time keeping calm by using empathy. Try to see the situation from the unpleasant person's point-of-view. In some cases, you may have a new lease on the situation by taking yourself out of your own perspective for a bit. Gossip is a quick route to rudeness. No one likes being talked about. Even if the subject in question isn't around to hear it, many people take offence to hearing people they know talked about in a negative light. If you want to avoid rudeness on your part, you should steer clear of interactions like this. Even if other people are gossiping, you should turn the other cheek. Those who are there to see you refuse the prospect will think more highly of you as a result. Modesty is a virtue for virtually all polite people. Some people are rude for the fact that they focus too much on themselves. This is most often an innocent fault, but it's one that can easily be avoided if you try to look at the conversation from both perspectives. Even if everything you're saying is gold, you'll still come across as rude if you don't think to hear the other person's side of things. As a general rule, people like to voice their opinions. They'll feel constricted if they can't get a word in. Listening is a skill, as real as any other. If you don't want to be rude, you'll need to have a fine command of listening. Active listening refers to a broad range of reactions that let the other person know you are giving him your fullest attention. This can include body language, such as nodding your head, or soft responses like repeating the gist of what the other person said can get this point across.

Summary:
Think before you speak. Monitor your voice. Demonstrate empathy in your conversation. Ignore gossip. Stay modest. Let the other person speak.