There is Nothing in this World that we can be Completely sure of.

I don't really have a good opening argument for this, so I'll simply let my opponent go first. Easy enough, no?

I'll propose two for you.

1. Existence exists

2. Law of non contradiction.

It should be noted that the ability to question something is no proof of its non validity. That is, just because you may be unsure of it, does not equate to its non absoluteness.

Haha, looks like I have my work cut out for me.
This should be fun.

Anyway,
"1. Existence exists"
Can you be completely sure? That is what this debate is all about, after all. Can you be sure that we truly exist, that we are not some non-existant beings that wish to exist? Can you be sure that, after all, we used to exist, but we do not exist any more? That this is all a simple by-product of a want to still exist? It's all completely possible.

"2. Law of non contradiction."
The law of non contradiction, which states that two opposing viewpoints cannot be both true at the same time, has nothing to do with it. At least, I don't see what it has anything to do with our debate. Would you be so kind as to explain why you proposed the law?

"It should be noted that the ability to question something is no proof of its non validity. That is, just because you may be unsure of it, does not equate to its non absoluteness."
However, the ability to question something with logical reason and proof is proof of it's non absoluteness.

(1)Existence exists - Objective reality.

Existence i.e. reality, requires no justification, as it is prior to and independent of consciousness. To exist is to be something - distinguished from nonexistence (nothing). It is to be an entity of a specific nature made of specific attributes. A is A. A cannot be non A.

Something exists which we perceive and we exist possessing consciousness - consciousness being the facility of perceiving what exists. Consciousness is a trait of biological entities which is an acquired awareness of an independently existing reality.

It follows then that if nothing exists there would be no consciousness - additionally a consciousness with nothing to be conscious of is contradictory in essence. Similarly, consciousness conscious of nothing but itself is again a contradiction. Prior to identifying itself as consciousness, it must be conscious of something.

Existence (set of all things) exists (trait of existence). As the trait exists this means:
Ontologically - essential to each valid concept is the reality of existence.
Epistemologically - existence is not artificial. That is, there is no situation in that what it identifies is not fact.

"Can you be sure that we truly exist, that we are not some non-existant beings that wish to exist? Can you be sure that, after all, we used to exist, but we do not exist any more? That this is all a simple by-product of a want to still exist? It's all completely possible."

So yes we can be sure by virtue of 1. Being conscious and 2. The law of non contradiction which entails A is A. A cannot be non A. Additionally it is impossible to argue non existence from the position of existence. Note this is not a proof of existence - it simply means (again Law of non contradiction) that you cannot exist and be able to argue successfully that you do not in fact exist. Likewise you cannot be in a state of non existence and perform any action (e.g. wish). A cannot be non A.

(2)Law of non contradiction

You wished to know how this is relevant to "There is Nothing in this World that we can be Completely sure of." Quite simply by identifying any entities properties we by default know with complete certainty a matching set of incompatible properties it cannot be.

"However, the ability to question something with logical reason and proof is proof of it's non absoluteness."

Deductive proof yes - use of logic only if it is correct. It is quite easy to use logic methods incorrectly. For example:

All elephants are mammals
A tiger is a mammal
-----------------------------------
All tigers are elephants.

It is logically structured but also unsound.

Well...

I guess you got me. Good job. It was fun. I know when to quit, and this is it. I have no arguments that could possibly prove you wrong.

Cool. I would like to debate you in the future sometime.

I'm glad you had fun. :D

Feel free to challenge me anytime - message me first though as my schedule may not be the most compliant.