This being a Japanese game, and a RPG at that, there is more than meets the eye when it comes to Chrono Trigger. There is one concept that is never explained in the game, it is only hinted at. The more astute players are supposed to work it out for themselves. Once the person understands this concept, he/she truly understands the game. Here I will give my view. Incidentally, the picture on the left is a picure of the Time Egg, which is better known as the Chrono Trigger!

The main question to be answered is who is the "entity" that is mentioned in the game? Robo, after 400 years of pondering, worked out that it wasn't Lavos that was creating the time gates. So who was it? Someone wanted the team to see the things that they were seeing. Why? Ayla suggested that this person was dying, and their life was flashing before their eyes, and they were regretting the bad things that had happened to them during their lifetime. This person also wanted the team to change these regretful things for the better, so they sent the team on a journey to put right what once went wrong.
This person, I firmly believe, is Queen Zeal. She is responsible for everything that happens in the game. She is posessed by Lavos, and does some pretty horrific things, which eventually lead to the destruction of the Earth. However, when she is defeated by Crono & co., and the first form of Lavos is destroyed, according to Gaspar, she reverts to a human being (her old self), and then dies. However, just before she dies, she remembers all the things that she has done, while she was posessed, and sends the team on their journey.
Thus, the game starts, when Lavos dies (i.e. the end), and after the end, comes the beginning. The beginning creates the end, and the end creates the beginning. The game is a tangled hierarchy, where A (the beginning) is created by B (the end), and B is simultaniously created by A. Interesting from a philosophical point of view. The game can never end, therefore, and in a way, it could be said that the game is a paradox. Wow, what a great game!