Riddle me this... What means everything to you, and nothing to anybody else?

I've decided to talk about wordplay here... because it's a topic that has always fascinated me, and seeing as I don't know any language yet other than English, I have no choice but to talk about that. I'm not aware of any other languages that have so many different meanings, spelling and interpretations of the same words, so seems the perfect place to start.

Four candles. Two words that mean nothing by themselves, but when said aloud and fast enough can lead to confusion. A hero of mine wrote that sketch, along with a million others using homophones, Freudian slips and every literary technique in the book, even going so far as to create some of his own.

Oh, and that's not all words can do. Poetry, somebody creating images and emotions with a few stanzas alone. Amazing.

I have always found that words have a hidden power of their own, they can wound, they can scar, bring down countries, empires, inspire revolutions, cause armies to fight to their death for you. Charisma is what caused the atrocities of the second world war, not guns and soldiers, they were merely tools.

But the true beauty of words for me lies in riddles. How somebody can say one thing and mean another, deliberately deceive, it's so perfect, illusion in its purest form.

I won't bother with St. Ives, everybody knows that. I could go into the 4 guys on a boat who each catch a fish and only end up with 3, but I tell it too often. Instead, here's one:

A cougar, a mountain lion, a puma and a panther are shot dead, but the hunter only carries back one body. Why?

P.S. sorry this isn't as smooth as my other blogs, I am slightly confused right now, my head hurts, I'm constantly exhausted with no reason as to why other than depression, which has no reason at all to be hitting so hard right now, and to top it all I can't even remember anything I've done for the past week. Oh.. and, answers are at the bottom of this, written in black so you'll have to highlight them. And this is green to symbolise the Riddler, not keeping it, sorry to disappoint those of you who thought I'd had a breakdown and decided to make this readable.

Answers: Your mind means everything. And they are all names for the same animal.