Personal power is the ability to go into other planes, to cross that threshold from one dimension to another. Why do that? Because it is there to do; knowledge, power, and beauty lie in those other worlds.
Mystical powers develop primarily through the raising of the kundalini. The Kundalini is a type of energy that exists within all things. It's possible to pull that energy, to mass it, to transmit it.
Siddha powers are a type of occult power, but occult powers come in many shapes and forms. The Siddha powers that you most commonly hear about are things like levitation, telepathy, and astral projection.
Occult powers, on the other hand, are much wider-ranging. They involve the ability to change dimensional structures and the evolutionary path of sentient beings.
There is this school of thought that says the usage of all mystical and occult powers is bad. I find that thought is usually propounded by people who don't have any powers. It's kind of a sour grapes attitude.
Life is the power to perceive. Without perception there is no life, and what is most endemic to perception is power.
Everything is dependent upon energy. Energy is attention. Attention is awareness.
If you have power, you might be able to heal a person. You could actually get inside their cell structures and create a change.
What will happen in those encounters? Who knows? It wouldn't be much fun if you knew all of that; you'd be watching an old video called your life.
