The book is:
Mindscan by Robert J. Sawyer
The 4 pages you want to read are all that is of Chapter 2.
some excerpt from that chapter:
"from the moment the synthetic body is activated, there will be two of you-two entities who each feel they are you.
...In your own mental picture of yourself, which one do you consider the real you: the one that suffers aches and pains, the one that has trouble sleeping through the night, the one that is frail and old? or the vigorous you, the you in full possession of all your mental and physical faculties?
...the human mind is nothing but software running on the hardware we call the brain.
...consider the fact that the atoms that make up your body are completely replaced every seven years: there's not one bit of the you who was once a baby that still exists; it's all been replaced.
What matters is the continuity of being....
I'm sure that even by my few quote's you now have a better idea of the concept.
So the only question is when can we start actually doing this?! I mean, I might not be able to go on but I know that my copied self would want to and what if we could have a copy of those we know and love around long after they died?!