A few questions

[Kyuuketsuki]

1. Do you think it is possible to know why the universe exists?

Probably not but a more interesting "take" on that is, "Does there actually have to be a why?"

2. How do you think morality can exist without objective authority or verification?

Morality is a system of ethics, ethics are social and variable so yes.

3. If there is no afterlife, what motivation would/should anyone have for living any particular way, such as trying to live ethically, civilly, healthily, or any specific way?

Because it makes sense to treat others fairly, it means they will tend to treat you the same, it means you have a "right" to expect that kind of treatment and it tends to help social animals like hums get along with each other without biting each other's heads off all the time.

4. If there is no afterlife and no essential or ultimate meaning to existence, why should an atheist care if someone believes in a religion and, indeed, if believing in a religion would make their life easier, would that bother you as an atheist?

Because it's a waste, because the time spent believing and praying is time that could be spent to the betterment of the human race and because it's f***ing irritating that belief without reason is held in a position if greater respect than being an objective rationalist.

5. Can you be absolutely certain, without a doubt, that God or something supernatural does not exist?

Nope, no more than you can be certain one does! Can you be certain there isn't a cream cake (the great mystic cream cake of creation) at the centre of the Earth?

Kyu