Now picture two apples. Can you picture three? Four? Four apples, almost instantly, are appearing in your head? Not two apples and then two apples. That's cheating. Five apples? Six? Seven? Sorry, but you didn't picture seven apples in your head. It's only possible if you're a genius. If you think that you're one of those geniuses, try again. Did you really picture seven apples in your head instantly and all at once?