Make your point. Always do. Do not hesitate. Of course, listen with the due respect. Make yourself a rule to answer in such a way that one word of yours corresponds to ten words of your counterparty. However, do make your point.
In the business world, you will be eaten up real fast if you will not have the guts to say what you think and further protect your point with the arguments. If the company is bigger than one man show, politics will play its role in your business life, and your position will be challenged by your peers, subordinates and bosses. The very best favor, you can do yourself, is self-development, which will strengthen your position and help to make your point more persuasively.
If the environment in your company makes it hard to make your point (no one listens, not healthy climate and culture, leaderism or other similar reasons) do change the environment. Including leaving the job. Go to your boss and make your point clear on this.
