Why Is Cryonics So Dismissed by the Scientific Community?

It is a fair question, and one I get often: if cryonics might actually work, why does mainstream science treat it as pseudoscience? We can already revive certain cells, tissues, and even whole organisms from a frozen or vitrified state. We have cooled people into deep hypothermia and brought them back. So where does the dismissal come from?

I cover this in depth in my book, The Science of Hope: Practical Cryonics, but here are the two reasons I think matter most. One is historical, the other philosophical.

Reason one: a historical schism

The dismissal is partly an accident of history. In the early days of cryonics, the Cryonics Society of California assembled a scientific advisory board that included genuine cryobiologists and cryogenics researchers. They agreed to lend their credibility on one condition: that the society not actually freeze anyone yet. The society, led by Bob Nelson, went ahead and froze a patient anyway. The advisory board disbanded, and the established field of cryobiology distanced itself from cryonics. That rift never really healed.

Timing made it worse. Cryonics predates the internet, cloning, the sequencing of the human genome, and modern AI. It was born when computers were still in their infancy. The core idea was brilliant precisely because it bet that revival would eventually become possible. But at the time, science had no plausible pathway to revival. Notions like molecular machines repairing a frozen body cell by cell were pure science fiction. So scientists were on safe ground calling revival impossible; it was, for all practical purposes, at least a century away. The trouble is that as new technology made revival look less and less far-fetched, mainstream science never went back and updated its verdict.

Reason two: science has no theory of you

The deeper reason is that science still has no real account of consciousness, of what makes you you. I do not mean a soul in the religious sense. I mean whatever it is, unique to each person's brain, that makes your experience yours and not someone else's.

Science tends to treat a person as simply their brain. But a brain is billions of cells, and those cells die and change constantly, yet you go on experiencing the world as the same person. Under the standard view, reviving someone means either repairing a frozen brain and body cell by cell, or transplanting a repaired brain into a cloned body. Both are extraordinarily hard.

If science could answer the fundamental question, why are you you and not someone else, the answer would probably point to some specific structure or pattern in the brain that ties it to the consciousness you experience. And if we understood that, restoring it into a healthy cloned brain might turn out to be far simpler than thawing and repairing a body cell by cell. But mainstream neuroscience rarely even admits how completely it lacks a fundamental understanding of consciousness. It is a bit like trying to build a nuclear bomb without knowing that molecules are made of atoms.

The part that makes me optimistic

I think science will eventually learn to decode the software of the brain, and I think it is the most extraordinary question left in all of science. A sequence of about three billion DNA base pairs encodes the blueprint for a network of billions of cells that somehow becomes sentient. How?

We already know the brain is organized into regions. The occipital lobe handles vision, and so on. But we cannot yet simulate a brain and say which neurons do which jobs. Cracking that may even require an entirely new scientific discipline. Still, the pieces are arriving: we are building ever more capable neural networks in AI, computation and storage and data-transfer speeds keep climbing, and researchers are already mapping the connectomes of simple organisms.

Once we genuinely understand how the brain's software works, how a physical network produces an experiencing self, I think we will finally be able to explain why we experience anything at all. That will not only be the key to immortality; I think it will reshape our understanding of reality as profoundly as evolution, DNA, or cell theory did. Some of what we learn may be unsettling, and I explore those implications in the book.

The reason that is not really about science

There is one more reason cryonics gets dismissed, though not by scientists: many people simply do not see death as something to be avoided. In much of Christianity, dying is arguably the best thing that can happen to you. My aunt is genuinely convinced she will die and go to heaven to be with God and her loved ones, and that this would be far better than being young and healthy in some future version of Earth. A lot of people, especially older people, feel that way.

I cannot claim certainty either. Maybe death is fine. But I am not going to stake that decision on assumptions I have no way to test. The choice between dying and living longer is not one you want to get wrong, and since death is unknown and a longer life could be wonderful, I will take the bet on cryonics. Especially because the people I love are alive now, and I hope to be preserved alongside them.