This is a great video explaining what would be considered the 4th dimension. Seems to be a computerized voice so its a bit hard to follow at times but it will give you a great perspective of what the 4th dimension would be like.

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So, does the 4th dimension exist ? how about the 2nd dimension ? and what actually lives in the 2nd dimension ? If the 2nd dimension is unaware of the 3rd dimension then would the 2nd dimension believe that a 3rd dimension exists. We know a 3rd dimension exists because we live in it, so is it acceptable to believe that a 4th dimension exists.

Imagine being able to see the 3rd dimension from a 4th dimension perspective, being able to see every possible outcome to every possible situation ? Could you even wrap your mind around that ? How much of our brain would we need to use in order to process all of this information ?

Feel free to comment with your own opinions.