Atheist: “I don’t have a worldview”
Answer: A worldview is simply how we interpret reality.
Every worldview can be distinguished by how it answers the following questions:
Origin--where did we come from?
Meaning--what is our purpose?
Morality--how can I know right from wrong?
Destiny--what happens when we die?
While everyone doesn't have a "religion", everyone has a "worldview". So, why are answers to these questions NECESSARY for a worldview? Because how one answers these questions are what DEFINES a worldview (i.e. how one interprets reality). If anyone contends with these questions being the most relevant questions to distinguish worldviews, they need to provide a set of questions that would do a better job distinguishing between worldviews.
Many atheists love to pigeonhole people that have a "religion" and mock them with clever caricatures of how a particular "religion"--Christianity is their favorite-- answers these questions.
But when the question(s) gets hit back to the atheist court, many atheists slither back into their hole of "isn't". If you don't have a more coherent and consistent (i.e. better) answer than the answer you are making fun of, then what grounds do you have to object? As C.S. Lewis said, "one cannot call a line crooked unless he has some idea of a straight line. "

Any rebuttal without a coherent counter-argument amounts to nothing beyond a childish "NUH-UH!". In short, it is like a wrestling match in midair--their is nothing solid (of substance) holding up an objection like that.
If you say, "I don't have an answer for those questions and I choose not to define them," that is fine; however, you have no grounds to object to anybody that does define answers to those questions no matter how ridiculous they may sound. Politely put down the microphone (or in this case the mouse) and go enjoy your hedonism.
Atheists love to conflate God with arbitrary made up things (that you don't believe in) like leprechauns or their favorite, the Flying Spaghetti Monster. Then they say, "You disbelieve in those things, I just go one step further in my disbelief." First, there are no good reasons to believe those things exist. Second, how one views God influences all these fundamental questions (i.e. their worldview). Whether or not someone believes in leprechauns, or any other arbitrary imaginary figure you try to conflate with God makes no difference to how one answers those fundamental questions.
Lastly, do not say, "I don't need to answer those questions because THERE ARE NO ANSWERS." This is begging the question. It amounts to the following:
"Naturalism is absolute. Therefore we can never know answers to those questions unless "SCIENCE (the god of naturalism)" tells us."
Remember, circular reasoning is when a reasoner BEGINS with what they are trying to end with. In this case the reasoner begins with the assumption that naturalism is an absolute, but that is the very thing we are trying to prove/end with. By doing this, the naturalist suppresses the angst in us all (that transcends borders) that begs for answers to these questions.
Why do atheists assume that science/scientists (e.g. Richard Dawkins, Sam Harris, and Lawrence Krauss) have not attempted to answer these questions?
1. The incoherence and inconsistency of the answers (that logically follows from naturalism) to these questions knocks naturalism off any legitimate contention of truth. As Sherlock Holmes once said, "...when you have eliminated the impossible, whatever remains, however improbable, must be the truth."
2. There are other worldviews that believe in some form of the "opposite" of naturalism/the impossible; however, it is the positive answers the Christian worldview provides to these fundamental questions—that cohere with reality while being logically consistent—that push the Christian worldview to the top of contention between ALL worldviews.
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