Ivo Babarovic:
What's fascinating to me is how science of consciousness, modern physics theories and description of deep meditative states come together. I just have a feeling that sometime in future this will all come together in one big theory. Still, one can again ask WHY? Hehehe.
Another thing just occurred to me: Maha Brahma is the first being who was born into this universe. After a while, he felt lonely and wished for other beings. Subsequently other beings were born, and Maha Brahma mistakenly assumed that his wish had created them. Suppose you could ask this very first being to exist in this universe why you exist. He would confidently tell you it's because he created you, and he would be honestly mistaken.
That story is part of what the Buddha taught. Here now comes my own little theory, and I believe I'm not the first one to come up with it: Our universe is part of a kind of computer simulation. Everything you are, and everything you have ever experienced in this life and in past lives, all that exists in no other way but as a "simulation run" on a big and complicated computer. The relationship between that big and complicated computer and us is not as in the movie "The Matrix," but rather it's like this: Suppose you typed some code into your laptop to create a program where little dots on the screen have the ability to interact in a certain way. You could do a simple gravity simulation, where they simply follow laws of inertia and gravitational attraction and move around on the screen, or you could make it so they could sense each other in different ways, process that data, develop strategies and behaviors, etc. If you make the program complicated enough so they can formulate, in their own, simulated minds, the question: What are we and why are we here? then you have the situation I'm talking about. They are nothing but data and rules running on a computer, which itself is totally outside the realm of their experience. Now let's say we are the dots and there is a big computer running our entire Samsara (our universe and the other universes the Buddha spoke of). Maybe some child programmed all this just because he likes to explore this new toy, the computer. That's the answer to your question Why. Maybe it wasn't a child. Maybe it's part of a doctoral dissertation. We don't know, but do we really care? Next you can ask: Why is the child or the PhD candidate in existence. What is the world/universe/samsara in which that being exists? The answer is simple: That entire world is a simulation running on a (probably even bigger and more complicated) computer. This paragraph is just a theory, although I personally think it's most plausible.
With all these thoughts, all these potential explanations/answers in mind, I ask you: Would you rather know the answer to the question WHY, or would you rather do some noting and go through some discomfort for a few months to see if stream entry doesn't do more for you than hearing someone answer your question?
It's a little bit like a choice between being right and being happy. However, once you get to the point where you see that the WHY question does not make as much sense as you thought, I'm pretty confident you won't feel like you were wrong to ask it in the first place. I like what tom moylan said. In a way, you could say the purpose of life is to look for answers to questions like, Who are we, What are we, What is going on, WHY!