The power to walk away

"Self-ownership (also known as sovereignty of the individual, individual sovereignty or individual autonomy) is the concept of property in one's own person, expressed as the moral or natural right of a person to have bodily integrity and be the exclusive controller of one's own body and life." -Wikipedia

Strive to achieve a position where no one can tell you what to do. I think one of the greatest powers to have is the power to walk away; to be so self-sufficient that you are not required to deal with something, you cannot be forced to do anything because you have the ability to do something else; you have the ability to not to give a shit. To be able to do something is to have power to do something, and to have power is to have strength. One of the most obvious manifestations of this is to have fuck-you-money (The name says it all)

If you have to do something, you are dependent on something. If you have options, you are independent, you can choose something else and leave the shittier option to be as it were because it has no effect on you, it has no power over you, thus can't overcome you, because you have more power, you are stronger; you are independent of it.

Let's take an example: A woman runs her mouth to provoke a fight between her bf and some other guy. The bf has to prove himself worthy, he has claim or hold on to the alpha status to gain her approval to acquire favors from her; the other guy has the ability look at the situation, shrug and walk away, since he really has nothing to gain/lose there. The woman clearly has power over the bf and that's what tickles her, that's why she wants the fight.
If the other guy has to prove himself so as not to appear beta or coward, because people are looking, then the crowd, including the woman have power over him. They have a grip on his ego. He cares what they think about him, he is dependent on their perception of him. He isn't in control of his own actions, everyone else is.

Tl;dr: Try not to build your life so other people can tell you what to do, or that you have explain yourself / your actions to them (i.e. argue) Independence = having power that you truly, solely own and control = strength.