We can't 'cure death' because biology is extremely complicated.
I think people see the products of modern technology, such as the International Space Station, the Hadron Collider, smart phones, skyscrapers, etc and think we're pretty sophisticated. Many people 'feel' like we should have a cure for cancer, and some people even invent conspiracies about pharmaceutical companies hiding the cure. I can understand, to some extent, why people feel this way. The modern world is an awesome place.
Unfortunately, when it comes to biology, we're still in the dark. One of the unsolved, fundamental questions in science is – what is the origin of life? We don't even fully understand how a single cell organism works. While the ISS and the Hadron Collider are both impressive accomplishments, their complexity is several orders of magnitude less than even the most simple organism. If we can't understand the basic questions about how a single cell organism works, how are we going to manipulate the fundamental processes that govern trillions of cells working in unison? That we have as many drugs and treatments as we do is the result of generations of scientists poking around in the dark until luckily stumbling on a drug or underlying mechanism of disease.
Without a fundamental understanding of how biological organisms work on a molecular level, we're left to educated guesses on how to fix things that are breaking in the human body. Trying to cure disease without a full understanding of the underlying principles is like trying to travel to the moon without using Newton's laws of motion.
The reason we haven't cured death is because we don't really understand life.
Justin Dragna, PhD in Chemistry from UT Austin
One reason we can't 'cure' 'death' is the bizarre tendency of so many people to use words like 'cure' and 'death' so inappropriately, leading to public failure to appreciate the possibility of medical interventions to postpone (maybe indefinitely) age-related, life-threatening ill-health. Why can't we dramatically postpone age-related, life-threatening ill-health yet? Because it's very hard to do, but also because people keep mis-stating the question.
Aubrey de Grey, PhD in Biology, University of Cambridge
Death is not curable because it is not a disease. In fact, it is the very nature of existence. We call it 'death' and attach dreadful associations to it because we are human. But every creature and plant must also go through that process.
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