A world without science.
"A world without science." The most obvious thing to do would be talk about how terrible it would be not to have electric lighting or computers. Or even explain how much of a difference medicine makes, and how glad I am I have access to antibiotics and aspirin. But I think there are other questions I need to ask first. Just to make sure I'm answering the right question, I'd like to make sure we agree on the meaning of all the words in the question
Since my essay title is "A world without science", I'd like to start with "science". What do you think science is? Is it the same as what people in the middle ages thought science was? Almost certainly not. Or your own grandparents? There are some things that I'm sure we all agree are science; for example combustion engines or electricity, but others are less clear. If electricity is science, then is fire? People have almost always used small amounts of technology. Even 'cave men' made flint knives and used friction to create sparks and light fires. The word atom is ancient Greek; the concept of an atom was thought up by an ancient Greek philosopher.
If all of these things are science, then I don't think I can imagine a world without science. Certainly not one with humans in it. And if we argue that some of these things aren't science, then maybe in the future some of what we say is science will no longer be counted as such, and so we are already living in a world without science.
Then again, even once you have an agreed definition for "science" you need to agree what "without science" means. Gravity wouldn't disappear if we knew less about it. It depends on how you see concepts. Do they exist separately from our knowledge of them? Does someone bring a concept into existence, or discover something that was always there? Newton's laws were true before he thought of them, but a concept has no solid from, no more than any thought. So until it's been thought there's nothing there.
I've almost managed to work out what the question is asking for. I may still be wrong, but I think that by "science" we probably mean either technology or human understanding of scientific concepts. Now, if it's concepts then I start asking, what is a scientific concept? People have always know things fall when you drop them. Is that science? Or did it suddenly become science when Newton wrote a set of formulae? As for technology, the wheel is definitely technology. And even before that, a spindle, or a knife, or thousands of other basic tools people have used for millennia.
We've now discussed the meaning of both "science" and "without science". It might also be interesting to discuss the meaning of "a world" as opposed to "the world", or even "a culture", but that would need another essay.
All in all, I don't think that people will ever live in a world completely without science, though they may use less than us. I still don't know if this is the answer you wanted or expected, but it's my genuine thoughts.