Why is there something instead of nothing?
Why is there something instead of nothing? is a philosophical question which ponders the existence of the universe. In particular, it implies that the universe is contingent, and seeks the underlying purpose for why one contingency happened rather than the other.
Why or How?
The word "why" implies a purpose, reason, or intent. If asked, "why did you go to the store?" the question is asking for the underlying purpose (perhaps to purchase groceries?). Whereas the question, "how did you go to the store?" is asking about the process of getting to the store (perhaps you took the bus?). In common speech, we often use "why" and "how" interchangeably, but, if we want to get specific answers, we have to ask specific questions.
Consider an arsonist burning down a house. We could ask, "how was the house burned down?" This has a valid answer: the arsonist use gasoline and matches. We could also ask "why was the house burned down?" This too has a valid answer: the arsonist wanted to collect insurance money.
However, consider a house burning down because it was struck by lightning. We could ask, "how was the house burned down?" This has a valid answer: lightning is extremely hot and when it struck the wooden house, it ignited. But, if we ask, "why was the house burned down?" This question is not valid; although people act with a purpose, lightning does not. There is no answer because the question doesn't make any sense. It's like asking, "how much does justice weigh?"
Natural phenomena appears to follow natural laws without an underlying purpose. Rivers converge on their way to the sea because of gravity, not because they're intent on meeting each other. A magnet is attracted to an iron bar because the the alignment of its atoms, not because it wants to give the bar a hug. The universe itself appears to be a natural phenomenon, and, like all other natural phenomena, it doesn't seem to have a purpose. We can impose a purpose on it, but that is our purpose, not the universe's purpose. This means we can ask questions about "how" the universe came to be, and physicists can give pretty satisfying answers, but, asking questions about "why" the universe came to be, at least for now, seem to be nonsensical.
Before we ask why the universe exists, we should first ask, "does the universe itself have a purpose?" Many people believe it does, but most of them disagree with each other, and, unfortunately, none of them are able to demonstrate why their answer is correct. Until we're able to come to a conclusion on whether the universe has a purpose, it doesn't make any sense to ask why the universe exists.
What Is Nothing?
The question "Why is there something instead of nothing?" implies that the universe is contingent — it could either exist or not exist — and, if history had played out differently, there would be nothing instead of the universe. Although this seemed like a perfectly valid assumption in the past, physicists have learned a rather startling fact about the universe: nothing doesn't exist.
At least it doesn't appear to. People used to believe there was nothing inside a vacuum and there was nothing in the void between the stars, but scientists have recently discovered everything which appears to be a empty is actually teeming of vacuum energy and virtual particles. The current understanding of the universe is that it's not possible to create a pocket of "nothing." No matter how hard we try to eliminate matter and energy, there is always something there.
Of course, this doesn't necessarily apply to things outside of the universe, but when we wonder about things outside of the universe, we are no longer talking from a point of intelligence, but rather blind speculation. Before a question like, "why is there something instead of nothing?" can be addressed, we must first answer the question, "is it even possible for there to be nothing?" So far, the answer seems to be "no."
The Unknown Isn't Evidence
When I hear this question, it's usually during a discussion regarding the origins of the universe, and the person asking the question is usually religious, or high, or both. Sometimes the person asking the question is legitimately interested in the answer, but far more frequently it's asked as a "gotcha" question where the person appears to be thinking along the lines of, "if you can't answer this question, I'm justified in believing my god created the universe."
This argument from ignorance has probably been around for thousands of years. No doubt, there was a conversation in ancient Greece like this:
- "Why do you think lightning exists?"
- "I think it's a mindless phenomena of nature, so it doesn't make sense to ask 'why' it exists, but maybe we could find out 'how' it works."
- "You're just ignoring the question. I believe lightning exists so Zeus can use it to smite people."
- "Unless you can give evidence for the existence of Zeus, your belief isn't justified."
- "My evidence is that lightning doesn't have to exist, yet it does. Therefore, lightning exists so Zeus can smite people!"
It should go without saying that, even if we could prove there is a purpose to the universe, and even if we could prove the universe is contingent, it still wouldn't make anyone's belief in a god any more justified.