If you want to end spam, you need to acknowledge that spam is an economic problem and spammers send out spam because they make money doing it.
So how are you going to do this? You do get modded "insightful" for this but in true business fashion you don't give any real solutions. Not even any hints to real solutions.Not even a solid and workable definition of what is spam, and what is not. Often spam is defined as "unsolicited' but what is "unsolicited" really? I put my e-mail address on my web site, asking people to contact me. Anyone can find the address and start sending e-mails on any topic - are these solicited or unsolicited? If you say it's solicited when about the web site, then when are they off topic?
Next, how are you going to distinguish a "spammer" making money off the e-mail messages from all the rest making money off of e-mail? So many legitimate news letters being sent around that result in making money. I have received many e-mails from people I didn't know yet asking me about my business, and whom I ended up doing business with - having found my contact in many different ways, e.g. from my listing at alibaba, which is also a common source of suspected scam e-mails.
Obviously a whitelist approach doesn't work.
Having people pay for sending/receiving e-mail doesn't work: who are you going to pay to? How are you going to pay? How to exchange payment information?
Maybe you can come up with working solutions to this. Solutions that only stop spammers (oh, and a clear definition of "spammer" would be good), but that leaves all other e-mail correspondence unaffected.