You all know the story of George Washington's axe? The handle has been replaced three times, the blade has been replaced twice. Not a single molecule of the original axe is present within it, yet there has been a continuity. Therefore George Washington's axe doesn't exist, because George Washington's axe only exists as a concept.
I don't believe that I have an immortal soul. I believe that I only exist as THIS mind in THIS body. But what is my mind? An ever-changing collection of thoughts, emotions and memories. Definitely not the same mind I had last night. But what is my body? A collection of roughly ten trillion cells, constantly dividing, dying, being replaced. Roughly every seven years, a new set of cells makes up my body. (Bone cells live up to 10 years). So this is not even the same body that I possessed seven years ago.
Who am I then? Same as George Washington's axe, I am a concept. In other words, I am an illusion.
The molecules that constitute the body of this illusion will be gobbled up by the sun about 7.5 billion years from now, when our very own Sun becomes a red giant and swells up to encompass the orbit of the Earth, that is, if our planet isn't already annihilated in the collision between the Milky Way and the Andromeda Galaxy, expected to take place 3 billion years from now.
Even if somehow humanity survives all this, we are doomed to what astrophysicists call "heat death", or the final thermodynamic state of the Universe, in which the Universe has achieved maximum entropy, and through expansion, not enough gravity exists to pull matter back together, and not enough energy exists to sustain motion or life.
So we are doomed either way we look at it. So... what's the meaning of life? Why do I go to work every morning and pay my bills? What is the point? We all know where it's headed. We're all already dead.
We can't control tectonic plates and geological changes. Land gets swallowed by the sea, the sea bed slides into the earth's mantle, plates collide and create mountain ranges. Ice ages destroy all vegetation and scrape the ground bare, global warming floods low-lying lands, and then new ice ages begin and the cycle goes on.
We are insignificant in the greater scheme of things.
That's when I remember saying that I'm an illusion anyway. So who cares about how it's going to end... what matters is that there is good wine and good beer and good food to be enjoyed, right here right now. Sure, we are overpopulated and we are destroying this planet. But this planet has had its share of cataclysmic extinction events in the past, and the Universe just kept on trucking. Should we protect the environment and preserve our health? Absolutely. But we are only buying time.