>>1
Well, like to paraphrase Newton, "if I have seen further than other men, it is because I have stood upon the shoulders of giants". What you may attain in your life is influenced by your conditions. Take a tremendous achiever like Bill Gates, and change his place of birth to Mogadishu, and I would expect to note a dramatic decrease in income.
Do you owe your nation for setting up the conditions that have allowed you to succeed? I would say yes, you do. How much? Uh... that's up to the nation to decide; luckily most people with access to the Intarweb live in nations which pay some lip-service to the idea of "no taxation without representation", so you personally have some say. Perhaps unfortunately, every other citizen of the country you live in has some say on your rate of taxation also. Why? Efficiencies of scale; if every individual could opt-in or opt-out of every social service, the systems of administration and enforcement to keep people from getting a "free ride" would be enormous. It's easier to just subscribe every single citizen to the same "benefit package", e.g., schools, roads, defense of property.
Now, if a majoritarian percentage of your nation wants to give some % of all taxes the government receives to those who don't have a job, you are once again compelled to go along with the majority. Why would anyone want a welfare system? Simply put, it polls like unemployment insurance. The more someone rates their possibility of being unemployed, the more likely they'll support social welfare. The less likely someone is to imagine themselves benefitting, the less likely they are to support it.