I am able to experience Piti Specifically the "weak rapture" mentioned in this wiki page, that causes me to have full bodily bliss and itself causes piloerection (goose bumps) I am able to do this at will without sitting in a meditation session, normally only when I am on my own but am able to do it while around others. There is no object or meditation object I focus on to evoke this feeling, just the presence in my being, no thought, as well as I am able to do this with my eyes open or closed, normally closed.
I am trying to find out how this relates to Jhana and what is its use, this wiki page is vague of course, though I know Piti is also a bojhangha Meaning a perquisite factor to liberation.
The fourth enlightenment factor is piti, rapture or happiness. This, too, is a mental property (cetasika) and is a quality which suffuses both the body and mind. The man lacking in this quality cannot proceed along the path to enlightenment. There will arise in him a sullen indifference to the dhamma, an aversion to the practice of meditation, and morbid manifestations. It is, therefore, very necessary that a man striving to attain enlightenment and final deliverance from the fetters of samsara, that repeated wandering, should endeavor to cultivate the all-important factor of happiness. No one can bestow on another the gift of happiness; each one has to build it up by effort, reflection, and concentrated activity. As happiness is a thing of the mind it should be sought not in external and material things though they may in a small way be instrumental.
I use Piti for when I feel mentally weak or sorrow from existence. Though I do not really know "what" it is or how I have cultivated this or how I am able to do this. From some things I have read before it has indicated that it IS a by-product or a part of a jhanic state, which would mean I have (somehow) attained at least the first Jhana but I do not feel this to be correct as I am not really skilled in formal meditation.
Just to add, a few times in my youth when I would retreat into myself in times of great sorrow I was able to experience a feeling like piti that gave bliss but it was in no way as strong as I am able to feel now.
Any opinions or understanding on what this is would be very much appreciated.