Namaste.
Tonight I am going to be lazy and just post the whole Shvetashvatara Upanishad.. The answer to all of your questions are in there and it should only take about 15-20 minutes to read it:
http://sivanandaonline.org/public_ht...section_id=590
I could not have said it any better myself!
I could totally live on the Shvetashvatara Upanishad, the Ribu Gita and the Vigyan Bhairav Tantra and not want to read another single thing in my life.
Tat Tvam Asi.