Freedom to influence?

We all know about freedom of speech, freedom of expression and freedom of whatever you can name it. I’m not too sure if we have freedom to influence? Which I see a lot of people are doing it, without knowing.

For instance, when one guy said the chick is hot, and another says she isn’t. They probably agree with each other, but the conversation doesn’t stop there. One or another will start telling another that how and why the chick is not hot. From then on, one is actually trying to influence another to take on his belief. Is that legal?

When I said to my friend that I’m don’t like to have a video wall after the second thought, they tried to tell me almost 100 reasons why it is good and how it will suit my house and all that. I didn’t move by the speech though, my light bulb just lighted up for this. I’m not sure if we should or can do this or not…