Why Everyone Manipulates People And Why It Is A Good Thing

I'll bet you think your opinions are your own, don't you? Unfortunately you're wrong. At least a large majority of your opinions aren't your own.
It is impossible for anyone to re-think every thought a literate society has had. Because of that our brains use caching system of sorts. Essentially if you hear something from someone you are likely to believe it, even if they are not an expert in that field. Your brain saves this information in a cache of sorts, waiting for the right time to bring it to the forefront of your mind. Since our brains only work at 200Hz max, we don't have the time or brainpower to rethink every thought we have, so we don't question much of our precached thoughts and responses.

You can probably see where I'm going with this.

Because our brains take a lot of what people say as the truth and cache it, a large amount of our precached thoughts are not--in fact--our own. Hence, your opinions and even your thoughts are not your own. For example, in regards to life, death...what's the first thing you think of? Probably that death gives meaning to life, which--if you actually think about it and don't just parrot precached thoughts--doesn't make any sense at all. Why would death give life meaning? We are prone to rationalize a bad thing that happens to everyone as a good thing. If, say, everyone got hit on the head by a baseball bat once a day. Given some time, the people of our fictionality reality would begin to rationalize this daily head-bopping as having some kind of beneficial value. If we brought you into this new society of cranially-deformed people and they tried to convince you of the benefits of being hit on the head once a day, would you be convinced and want to join them? Absolutely not. Likewise, if you tried to tout the values of death to an immortal there is no way they would want to give up their immortality.
This is an example of a precached thought that society has loaded everyone with, and there are many others.

How does this relate to how everyone manipulates people, you ask? Simply put, if someone tells you a thought and you accept it as true and load it into your brain's cache, they have just changed your thinking and future reactions to people on the subject. Manipulation. Now, obviously most people do not do this on purpose, but they still do it. In fact, it is a good thing. It is how society has passed down information and culture for thousands of years.

Now, on to a slightly more traditional view of manipulation: getting people to think what you want them to think. Everyone does this, too. Why do you dress nicely for work? To make people think that you are smarter and are more in control of your job that you actually are. Why do you dress up for church? So people will think that your life is nothing but a happy paradise, just like everyone else's. Why are you nice to people at all? So they will think better of you. All of this is you trying to get people to think what you want them to think: that you are a good, wholesome, and smart person. Otherwise known as getting people to like you.