It sounds impossibly wishy washy, but this is a simultaneously precise and all-encompassing question.
We tend to take our existence for granted, because we spend most of it doing things like catching buses and scrolling through Twitter, but the very presence of, not only us, but the universe in general, is reliant on a very specific set of physical laws coming together.
The thing is, there's absolutely nothing about physics that suggests it has to be this way, it's, as far as we know, an incredibly unlikely accident.
We don't know, for example, why there appears to be way more matter than antimatter. The two are created in the same events, and should by all rights, annihilate one another immediately. And yet, here we are, surrounded by a universe made of matter. Had one of the fundamental laws be tuned slightly differently, the universe would never have come into being, matter would have disintegrated, or never formed in the first place.
Obviously, you could argue that, had the universe turned out that way, there would be no one there to observe it. We are only able to question the bizarre serendipity of our situation, by virtue of that serendipity.
Even then, it doesn't make it any less unlikely, and "unlikely" is generally not a scientist's favour word. There may well be an underlying reason as to why a universe should form at all, but for now we'll just have to be thankful that it did.
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