How do I know that something self-evident is true? My perceptions could be real or simulations or hallucinations or dreams or illusions.

How can a duck's consciousness be replaced by an alien? Is consciousness something separate from the body that can be put in different bodies or is it something emergent as a result of brain activities?

I agree that a shapeshifting alien could be pretending to be a duck and we would not be able to tell without analysing blood samples, etc.

I agree with you.

I agree with you.

I am not convinced that reality works in a way that requires absolute uncertainty to exist for absolute certainty to exist. The two ends of the electromagnetic spectrum https://en.wikipedia.org/wiki/Electromagnetic_spectrum are not total opposites of each other. Also, just because energy cannot be created or destroyed it does not mean that it is finite. There could be an infinite amount of energy spread across an infinite number of universes.

I agree with you.

I agree with you.

Thank you very much for your explanation. I understand now. I agree with you.

I agree that "the percentage is there more as an adjective than a mathematical relationship."

I agree that I am certain that we are communicating in English as opposed to any other language. Thoughts, emotions, perceptions, recollections, etc. exist even though we don't know whether souls exist or not and whether brains really exist or not.

You are most welcome.

1 + 1 = 2. 1 + 1 does not equal 4. Two people can become parents of two children and that would cause the number of people in that family to increase to 4. That does not change the math 1 + 1 = 2. The math in that case is 1 + 1 + 1 + 1 = 4.

I agree that religious beliefs are faith-based rather than evidence-based. Religions contradict themselves and each other. Please see: https://skepticsannotatedbible.com and https://www.evilbible.com

However, if our perceived reality is not actually real, then science can't be relied upon to give us facts. Science assumes that what we observe is real and not simulated or dreamt or hallucinated, etc. It is not possible for me to know with complete certainty that my body, other humans, non-human organisms, the Earth and the rest of the Universe actually exist.

According to Hinduism, our perceived world is an illusion called Maya. It is created by the Hindu Gods to test living things. It is impossible to prove or disprove this claim.

I agree with your example of the pickles.

I agree with you.

I agree with you.

I have never witnessed souls either. I am an agnostic regarding the existence of Gods, souls, reincarnation, resurrection, karma, etc.

I agree with you.

I agree with you.

By "100% certain" I mean completely certain. I am completely certain that I am conscious. I am almost completely certain that I will die.

Thank you for giving me more food for thought.

Yes, at least, I do. I can't speak for you or others.

You are right.

Excellent point. It is possible that the self is an illusion and thoughts and emotions and words and actions simply happen as a result of brain activities.

Here are some things I have done, currently do or will do even though I don't want to do them:

1. Breathe
2. Eat
3. Drink
4. Sleep
5. Dream
7. Pee
8. Poo
9. Fart
10. Burp
11. Sneeze
12. Cough
13. Age
14. Get ill
15. Get injured
16. Sweat
17. Cry
18. Suffer
19. Snore
20. Think
21. Feel
22. Choose
23. Be conceived
24. Be born
25. Remember some events that I don't want to remember
26. Forget information that I want to remember
27. Die

What I really want to do is go back in time and prevent all suffering, inequality, injustice, and deaths and make all living things forever happy but I can't do it. I am doing things I don't want to do. I can't do what I want to do. So, how can I have free will?

Thank you for your question. I am 100% certain that I am conscious because I am experiencing being conscious. It's a fact that is undeniable to me. Although, I can't prove to others (if they really exist) that I am not a Philosophical Zombie https://en.wikipedia.org/wiki/Philosophical_zombie - if others really exist they can't prove to me that they are not philosophical zombies either.

Thank you "punos" for your thoughtful reply. I am not a physicist, so please excuse my ignorance. Why would a proton be affected by other particles in a 5 light seconds radius? Surely, the zone of being affected would be mere millimetres or even less?

Thank you for your thoughtful reply. I find uncertainty difficult but I have no way to be certain of anything except for one fact: I am conscious. I am 99.99% certain that I will die but I can't be 100% certain of it until I have died. If it was up to me, all living things would be forever happy and there would not be any suffering, inequality, injustice, and deaths. Sadly, it is not up to me.

Thank you for watching the video and for sharing your thought about it. You can watch the full video here if you want to https://www.youtube.com/watch?v=nhvAAvwS-UA&t=135s

You are most welcome "Corvus." If souls exist, it is possible that souls reincarnate or resurrect after death of the body. I don't know if souls exist or not.

Thank you "Corvus" for your reply. I am 99.99% certain that I will die but I can't be 100% certain of it until I have died. If it was up to me, all living things would be forever happy and there would not be any suffering, inequality, injustice, and deaths. Sadly, it is not up to me. How would I know if others really exist? How would I know if others are really conscious or are actually philosophical zombies?

Thank you for your reply "Art48." I am 100% certain that I am conscious. No infinite regress is involved with this. Did you watch the Robert Sapolsky video excerpt? If so, what do you think?

Thank you "Tom Storm" and "Philosophism" for your replies. You have given me much to think about. So, is my perceived reality actually real or not? Do I have free will or not? Am I right to be a vegan or not? Am I right to be an agnostic or not? How would I know? This video: https://www.youtube.com/watch?v=uaxHTYtSavc is fascinating. Is Robert Sapolsky right?

Thank you for your reply "Outlander." It is more accurate to say, "Like minds think alike." It is the fact that they think alike that makes their minds alike.

Thank you for your reply "flannel jesus." How would I calculate what percentage of certainty I assign to things such as the objective existence of my body, other humans, non-human organisms, the Earth and the rest of the universe?