My job does not require materials as such. Should I work for free for the good of mankind? How would I be able to obtain sustenance and shelter?
This view was inspired by a documentary (called Zeitgeist if I'm right), where machines provide subsistance to humans, so humans can focus on creative and artistic tasks without having to focus (including science).
It's a far-fetched view, but in the long-term, I believe (and again, it's just a personal belief) that sharing is caring and that caring is very important. You certainly need a way of subsistance but I see that the incentive are incorrect.
The person who fixes the door locks for example, has incentive to charge you the most and make the process as difficult as possible, not to go the fastest away from your place.
I'm in favour of a system where everyone gets a basic income (to subsist for shelter, food and all basic needs) and they can (but don't have to) work if they want extra money.
You're right, not all the pieces fit together, but it's an interesting thought to start with :)
There is going to be new threats that show up (covid is a great example / alien attack is on the other end of the spectrum) - how do you plan to protect against these? Are you willing to leave these to volunteer willpower?
If you also notice the set of folks for whom subsistence is guaranteed (countries with good social nets / folks who have made enough money) keep working and trying to climb up the ladder. Do you think there is a baser instinct here (peacocking / self reliance / pessimism about future ...) at work?
At some point, you have to move away from the 'spherical chicken in a vacuum' arguments to have a reasonable discussion :)