It really isn't as easy as you'd think being the smartest man ever. I don't mean the smartest man you know, or the smartest man in one's state or nation, but of the entire human race, from the beginning to the end, the most intelligent component, hands-down. It's common practice to call someone who thinks of themselves this way a 'know-it-all'. I take this in stride. It's an accurate descriptor, in spite of sarcastic use: I literally know it all. It's considered somewhat egotist to claim you are the smartest person ever born, but that's not at all fair if you really are. It would be like claiming someone was being egotist for correctly stating that they have blond hair. If I had a quarter for every thing I knew, I'd be richer than Bill Gates in addition to being smarter than him.
At first glance, you might assume that I am being an idle braggart. I assure that this is not at all the case. It would be easier to illustrate with a few brief anecdotes. At the precocious age of one and one half, I learned how to read, write, add, subtract, multiply, divide, speak rudimentary Swahili, and use the toilet. Three of these things I have grown somewhat rusty on and I leave it as an exercise to the reader to divine which. In 1990, at three years old, I was narrowly foiled in publishing a scientific tract which would have revolutionized the field of biology by the rude revelation of a similar work having been published by Charles Darwin a mere hundred and fifty one years previous. I consider this my sole failure and even then it remains qualified; his theory of evolution was published about six generations earlier and has thereby become the foundation of most modern biological science, but mine was not subject to Wallace's Paradox, so we're pretty much even. In addition, the primary animals in study were, rather than birds and turtles, dinosaurs, which are awesome. I studied the fearsome oriental art of jiu-jitsu at the age of six, and in so doing learned that the martial arts consist of someone calling you Andrew and beating you with a bamboo staff; at the same age I learned quite a bit about life in the desert, such as how to catch lizards with a little noose made of black suture, that catching monitor lizards this way is a bad way without gloves because it leads to biting and crying, and that if you have any reptile friends in a terraneum, you need but add an adult toad to become lonely and alone overnight. So very lonely.
After the conclusion of my brilliant early years I engaged in a stint on the tropical island of Dominica. They claim to have 365 rivers, only one of which has chopped cadaver in it from a prank gone horribly right. One of the first things I learned there, in fact, was the value of a good prank: as my father was there as a medical student, it was often we discussed such hilarious japes as George, who attended a class in effigy; Stella, who pulled the old ink-on-the-microscope stunt, and Adam, who burned down the anatomy lab. Who dumped the corpses into the river remains a mystery to me, but I hear people there still want to get their hands on them to congratulate them on a job well-done. While there, I also learned that my deeply racist grandfather has a mulatto second cousin, that the revolution of the proletariat is historically inevitable, and how to properly use a machete.
 I also learned that girl cats and boy cats are different in a very specific way, although that difference being more or less universal eluded me for some time longer.
Soon I would return to the United States. It was then that I discovered the Internet. I had been using computers since the age of two,  but the idea of the Internet was new. With it I discovered three new things: the wealth of information available from around the world, the fact that I am readily the smartest person ever, and pornography. It was through the Internet that I went from knowing more than anyone alive to literally knowing everything man is meant to know, and some things besides. 
The knowledge gained thus far through the Internet has included how to tie a tie, conjugate French verbs in the imperfect tense, defeat James Bond, turn a bag of flour into three separate and distinct kinds of deadly weapon, win a knife-fight, inspire fear in evil dogs, courage in good dogs, and befuddlement in the Chinese, grant plenary indulgences, sabotage the war effort, properly assemble a team of superheroes, induce jaundice while in otherwise good health using cordite, visually emulate a nuclear blast with sufficient quantities of fuel, force a pig to fly, floss, defeat Xeno's paradox, evade taxes, teach the value of a dollar to schoolchildren and the elderly, win an election in Canada, become an American dictator by constitutionally legal means, force an economic model to work properly through sacrifices to one or both of voodoo god Bondye and voodoo economist Milton Friedman, build a space ladder given a trillion dollars and twenty years, invoke posse comitatus, annotate Herodotus, irritate Jack White, imitate Jack Black, dominate blackjack, and lose euchre. 
For me, the declaration 'I know something you don't know' is tautological, the taunt 'That's for me to know and you to find out' is redundant, and the proverb 'He who wants to fight will find a cudgel' is Slovakian. 
The only thing I don't know of is anything I don't know.
I have run into some difficulties having a greater intellect than all that lives, mostly because people are really arrogant. If I had a quarter for every person who, in a state of arrant hubris, has made the nigh-on-blasphemous claim they are smarter than I, I would probably have enough to buy a large pizza, unless the quarters were Australian, in which case I would have to settle for a couple of slices. That might not seem like a lot of quarters, but it is. 
They are usually my contemporaries, but I have on occasion run into those who, though old enough to know better, are either hell-bent on being wrong or just plain dumb. One instructor -- a doctor in children's literature, no less! -- attempted to convince a group of my impressionable comrades that the Bedouins, Berbers, and Moors could all be lumped into the same ethnic group as Arabs. I proceeded both to prove her wrong and to posit that she signed all official documents with an 'X'.

In addition to knowing everything that is true, I also know everything that is false. Some good examples: cows are native to Antarctica, JEB Stuart invented the machine-gun, and the goal of chinese checkers is to kill or incapacitate your opponent. I am also a fan of coincidences. Both Rimsky-Korsakov's Scheherazade and Lynyrd Skynyrd's Free Bird clock in at 10 minutes 8 seconds. Coincidence? I think so!

While I do, in fact, know everything, there is not time in the world to tell even the most enlightened audience half of it, but I feel the above makes a fine summary. So I shall merely conclude, as I am wont to do, by quoting Marx: 'Last words are for fools who haven't said enough already.’