Princess Celestia shot up and Princess Luna jumped back to avoid her sharp horn poking through her. "I was just about to wake you my sister," Princess Luna said as she sat down at Celestia's bedside. "You've only been asleep for an hour or so and I was walking to the terrace so that I may lift off into the night but I heard sounds coming from your room and thought you may have been hurt. I... I don't know if it will do much, but I brought you this glass of water." Princess Luna cutely offered the glass to Celestia.
Princess Celestia giggled under her breath and graciously accepted the glass of water. "Thank you for your concern my sister. I'm glad to know you've got such a keen ear," she leaned up and gave her sister an affectionate hug.
Luna sat down on the edge of the bed and was quiet as she watched Princess Celestia drink her water rather quickly. She knew that something must be troubling her. Perhaps it was another one of her dreams? "So..." Princess Luna as she began and kicked her hoof over the floor, "Could I ask what it was this time?"
"Oh, it was another one of those horrid dreams with those... with those terrible creatures that stand on two legs," Princess Celestia was eager to explain her dream to her sister for she knew that she was the one pony she could trust with her deepest feelings, "I... I dreamed we were in this huge room. Surrounded by all kinds of those creatures, and these weird flashing boxes too."
Princess Celestia chuckled as she finished her water and leaned back against the headboard as she finished summarizing the dream. "Well if those creatures need advice from you they must not be that intelligent," Princess Luna joked with her sister.
"Oh hush," Princess Celestia playfully swatted at her sister. After a few more jokes and some more light-hearted chuckling Princess Luna insisted it was time to go on her rounds. "Be careful Luna," Princess Celestia said as she waved Princess Luna off from her personal balcony, "I love you," she whispered too late as Luna took off into the night sky.
Princess Celestia rubbed her forehead and closed the doors to the balcony and headed back towards her bed where she crawled under the sheets and tried to get back to sleep. No matter how hard she tried to though, all she could do was toss and turn. Why did she keep having these dreams? Was she really giving some creature somewhere else political advice in her dreams, or was it a "simple dream" as Luna put it? If that was so, why did she have them in succession? She had heard of such things happening, two ponies sharing an experience in their dreams and that dream possibly manifesting into reality, but was that the case here? Were these hideous upright walking creatures in her dreams even real? Now wasn't the time to think about it. Princess Celestia was exhausted after the day's work and if that sun was ever going to rise the next day she would need her rest. She snuggled up under the covers and eventually fell asleep.
Over the next few days she continued to have the dreams, but one day they just stopped. She no longer saw the fragile looking creature in her uncontrollable dreams, she no longer saw the strange fluttering flag designs, nor did she hear the heated political discussions over things she didn't even know about in real life but knew about perfectly in her dreams again.
With each dream she had, she was sure to keep it recorded in her diary for future reference. One day as she read them over, she couldn't help but long for what she had dreamed of. Massive diplomatic interaction between other nations, big towering cities that could be seen from what seemed like miles away, and so many other things she saw that would make life for her subjects easier; it pained her to see an Earth Pony tilling the ground with his muscles. But then again, there were these other... things she saw. In one dream she saw this huge, roaring bird fly over a group of them, her and several of those creatures, and drop something out of itself. A huge explosion came after whatever it was hit the ground. The awesome power of it was enough to send shudders through her entire body even though she knew it was just a dream. The thought of a million, maybe a billion lives ended in the blink of an eye scared her. So long as she breathed, such a force would never find itself in Equestria.
As the hours of study of her own dreams progressed on, Princess Celestia eventually got creative. She made up a name for those strange, upright walking creatures who yelled, intelligently built their cities, and created devices which could end life faster than it begins. "Humans" she called them. She didn't know where the name came from, but it came to her quick, almost as if the second she started to create a name. What troubled her the most though was that not even she knew if she had created it or remembered it. Finally, there was that last choice that she struggled with. Somewhere on the page of each description of each dream, she had two check boxes. One was labeled "Good Dream" and the other "Horrible Nightmare". For the series as a whole, she just couldn't make up her mind. She would check one box only to tell herself that it was wrong as she would be reminded by the different visions of what she saw.
Eventually though, she made her mind and with a shrug selected both boxes. Yes, it would seem that humans were both "Good Dreams" and "Horrible Nightmares".