If I want to mine bitcoin and make transaction in bitcoin to whoever is willing to accept them, no government whatsoever as any power on me or the other person involved.
It's like wanting to tax someone for trading a potatoe for a cabbage.
Agreed. It is an interesting point that you make, bartering in 'produce' would be difficult for the government to tax. What are they going to do?
Cut the thing in half?

There is no selling price "5. Tax deducted from selling price". This law only applies to trades done with money.
The key to the law is here "and pays, or becomes liable to pay, the tax imposed under this section". For a person to become liable to 'pay', there needs to be money involved. No money, no liability.