The above thought is based on the following.
1. The first jhana has five factors: (a) Directed thought (vitakka): Think of the breath until you can recognize it clearly without getting distracted. (b) Singleness of object (ekaggatarammana): Keep the mind with the breath. Don't let it stray after other objects. Watch over your thoughts so that they deal only with the breath to the point where the breath becomes comfortable. (The mind becomes one, at rest with the breath.) (c) Evaluation (vicara): Gain a sense of how to let this comfortable breath sensation spread and co-ordinate with the other breath sensations in the body. Let these breath sensations spread until they all merge. Once the body has been soothed by the breath, feelings of pain will grow calm. The body will be filled with good breath energy. (The mind is focused exclusively on issues connected with the breath.)
These three qualities must be brought together to bear on the same stream of breathing for the first jhana to arise. This stream of breathing can then take you all the way to the fourth jhana.http://www.accesstoinsight.org/lib/thai/lee/eyeof.html
We don't have to call it First Jhana,  Second Jhana, third Jhana and so on, let's just call it "a peaceful mind." As the mind becomes progressively calmer it will dispense with vitakka and vicara, leaving only rapture and happiness. Why does the mind discard vitakka and vicara? This is because, as the mind becomes more refined, the activity of vitakka and vicara is too coarse to remain. At this stage, as the mind leaves off vitakka and vicara, feelings of great rapture can arise, tears may gush out. But as the samadhi deepens rapture, too, is discarded, leaving only happiness and one-pointedness, until finally even happiness goes and the mind reaches its greatest refinement. There are only equanimity and one-pointedness, all else has been left behind. The mind stands unmoving.http://www.accesstoinsight.org/lib/thai ... steof.html