Check against delivery.
Seventy-five years ago, Niels Bohr wrote a letter. This was in the wake of two world wars as well as both nuclear discovery and nuclear destruction.
He wrote his letter not just as a physicist, but as a citizen of the world. As a human being.
He had seen how his own scientific discoveries had been turned into weapons of mass destruction. And he saw – probably more clearly than most – that knowledge could both save and endanger our civilization.
So he called upon world leaders to warn them and to show them a clear path.
He wrote – and I quote:
“The promises and dangers involved in the technical advances have now most forcibly stressed the need for decisive steps toward openness as a primary condition for the progress and protection of civilization“.
He believed to his very core that the only way forward was an almost radical openness. Transparency and collaboration.
And his words still resonate. Perhaps even more urgently today.
A security imperative
Bohr’s call for openness was more than an abstract dream. It was even more than an ideological ideal.
For him openness was a security imperative grounded in science and pragmatism.
He understood that secrecy breeds fear and fear breeds division.
Openness, by contrast, builds trust. And trust is the foundation for both science and lasting peace between nations.
For him, the open exchange of knowledge was the very condition for survival.
At the time, his ideas were met with scepticism. The Cold War was hardening, alliances were forming and mistrust was spreading like a shadow over science and over the world itself.
A situation that is sadly all too recognisable today.
75 years after Bohr’s letter, we find ourselves in a very different world. Yet we face strikingly similar dilemmas.
The Cold War is behind us. The Berlin Wall has fallen. The European Union is more integrated than ever. But global trust is under strain.
We want to protect free and open research, but the world around us feels less open than before.
We see it in the race for new technologies. Bohr wrote his letter in the Atomic Age but his thoughts are just as relevant in the age of artificial intelligence, quantum computing, biotechnology and space.
Knowledge is becoming a field of competition as much as cooperation.
Countries talk about “strategic autonomy”, about protecting data, about securing research.
And they are right to do so. Responsibility matters.
But it is a balancing act. A paradox.
If we let the language of security erode the spirit of openness. If every idea becomes a potential threat. Then how long before the space for free inquiry begins to shrink?
Research security is essential. In an uncertain world, we must protect both ourselves and the knowledge we create.
But security must always serve science – never control it. And when it does, it strengthens not only science, but also openness. Too often, research security is framed as a barrier to collaboration. In our reality, it can build the foundation of trust that true openness depends on.
Real sovereignty in the twenty-first century means setting our own high standards for collaboration.
It means engaging with the world from a position of confidence. Not by closing our doors, but by opening them wisely. Welcoming trusted partners into collaborations built on both openness and safety.
And in Europe, we have a special role to play.
Because one thing is very different from the time when Bohr wrote his letter. Europe is now a stable continent in an unstable world.
The EU in many ways is the living embodiment of Bohr’s dream. An open integrated collaboration between different nations. A peace project as well as a scientific partnership.
We have institutions rooted in the rule of law, in democracy and in the conviction that ideas are stronger than fear.
Academic freedom is a European tradition.
And it is precisely this freedom that we must protect against the rising tide of censorship and surveillance elsewhere.
Openness is what allows European science to flourish and it will make Europe stronger.
The future of openness
But what does openness mean for the next generation of researchers?
For young researchers today, the world must feel at once boundless and constrained.
Scientists can collaborate across continents in real time. Yet they must navigate increasingly political and ethical barriers.
They face global challenges that Bohr could scarcely imagine: Climate change, biodiversity loss, AI, global health, misinformation.
And still, the core question remains the same: How can knowledge serve humanity?
Our task as policymakers is to ensure that researchers have the freedom, the support and the trust to answer that question in their own time.
That means long-term investments. In research, in education, in international partnerships.
It means creating frameworks that protect openness while upholding ethical responsibility.
It means believing that curiosity — that very human desire to understand the world — is itself a force for peace.
Because openness is about more than access to data or mobility between institutions. It is about attitude. About generosity of mind and of spirit.
Every generation must rediscover it. Every generation must defend it.
So, to the young scientists here today: You are the heirs to Bohr’s vision. You carry his intellectual legacy, but also his moral one.
When you collaborate across borders, when you share your results, when you challenge conventional wisdom. You keep the spirit of an open world alive.
Bohr sent his letter to the leaders of the great powers. Urging them to build peace through transparency.
Most never replied. And the following decades of cold warfare showed that his message was not taken to heart.
But history has proved him right.
Every major step toward peace and prosperity, from scientific cooperation in space to global climate agreements, has been built on dialogue and trust.
Every major failure has by contrast come from secrecy, suspicion and fear.
Bohr’s vision was never meant to be easy. It was meant to be enduring.
He knew that openness is a choice. One that must be made again and again.
Today, in an age of disinformation, division and geopolitical tension, that choice is once more before us.
Do we turn inward, protect what is “ours” and retreat behind walls? Or do we look outward, embrace responsibility and build bridges through knowledge with people and nations who share our ideals?
I believe the answer to that question will define our time.
We can see Bohr’s open letter as merely a historical document or we can see it as a living challenge. A call to action.
A call to keep science free. To keep dialogue alive. To keep our world open and our civilisation safe.
If we believe in those ideals. If we have the courage to act on them. Then legacy of Bohr will live on through us.
Thank you.