When introduced with such friendly words, it is tempting to put aside my prepared speech and instead to wander down memory lane with the honourable Professor Plesiu. Before I became Federal President, I travelled to Romania on various occasions, above all to assist the men and women who were doing their utmost to ensure that the past deeds of the Securitate were fully examined.

But today, only a few days before one of the larger European countries is to cast a vote of decisive importance, I would rather reflect on the state of Europe and our relationship with Europe. I therefore trust you will forgive me, Professor Plesiu, if I resist your kind invitation to share a few more of our reminiscences with this audience.

For even without the current situation in the UK, Europe would have cause to reflect on its form and its structure, and on people’s relationship with the European project.

Of course, talking about Europe in Paris, for example, is not the same as talking about it in London or Madrid, in Warsaw or Bucharest. As we see, Europe always looks a little different, depending on where we’re standing. This is of course partly due to the continent’s multifaceted nature, to the varied national histories, to differences in expectations and experience, and to the people’s varied hopes and disappointments.

If I, with my Berliner’s eyes, look at Europe from this standpoint in Bucharest, that may give rise to a few points of view that we could talk about briefly later.

Nearly ten years ago, Romania and Bulgaria became members of the European Union. May I remind you for a moment how differently we saw the future and Europe back then, both in Bucharest and in Berlin? That was also the year of the fiftieth anniversary of the Rome Treaties being signed. Half a century after the relatively humble beginnings of the ambitious European project, almost the entire continent had been brought together into this great community.

That was indeed cause for optimism – if I remember rightly, even more so among the new member states than among those who had been travelling together for a while. Especially here, in eastern and south-eastern Europe, an exceptional mood of enthusiasm for Europe took hold, a mood that was noted in the West with some astonishment. But of course the people here in these new member states were focused on the opportunities that were opening up for their societies.

I know that, particularly here in Romania, people weren’t simply looking at the economic advantages, such as EU grants; they also saw what opportunities for inward renewal and reform lay in EU membership, for example as regards anti-corruption efforts and the process of dealing with the Communist past. Both these endeavours were embarked upon, and progress has been made, especially recently. The European promise of a brighter future for all unleashed energies, even though it was clear from the start that lasting successes would not be quickly achieved.

In spring 2007, new and old members were united in feeling extremely satisfied with what had been gained; together, new and old members looked to the future with confidence. You can see that in the Berlin Declaration issued to mark the fiftieth anniversary of the Rome Treaties: "For centuries Europe has been an idea, holding out hope of peace and understanding. That hope has been fulfilled." And looking to the future, it says, "Our history reminds us that we must protect this for the good of future generations."

In differentiating between old and new members there, I was referring only to their respective dates of accession, for it goes without saying that all EU member states have an equal place in shaping the Union.

What does distinguish some of the younger member states from the older ones nowadays is their very particular outlook on Europe. Many people here in Romania have retained something of the enthusiasm of 2007. To this day, there are only a few in your country who doubt the value of the European Union – unlike in some other countries. Determinedly Eurosceptic parties play a very minor role. Many Romanians want more Europe, not less. This is another contrast with many other European countries. We need only consider Romania’s desire to join the Schengen area. Many also know that the European Union contributes significantly to development in their country and supports reform, such as in the justice system. Early this year, the European Commission recognised the successes Romania had achieved but also pointed out where action was still required. I know that all the people in your country working for the rule of law and the independence of the judiciary are grateful for the support they have from Europe. I wish that this faith in the Union, this enthusiasm for the European project, were more widespread in other member states as well.

But in many parts of Europe, the euphoria of 2007 was followed by disenchantment. Just a few months after the Berlin Declaration was adopted, European solidarity found itself facing its first, major challenges – during the severe financial and economic crisis. Its consequences and the difficulties generated by the management of that crisis had not yet been completely dealt with when a new challenge arose from the open breach of international law right in the EU’s immediate neighbourhood. And now, particularly since last summer, the movement of refugees has been really testing Europe’s mettle.

All these crises have shaken the EU to the core and thus sparked another crisis, and a particularly serious one at that: a crisis of confidence. The belief that the EU would eventually manage to overcome differences and build common ground seems, in many places, to be ebbing away. Some of the newer members in particular are wondering when the prosperity that membership promised will actually arrive. At the same time, there are political forces in many member states picking up on or generating that anti-European sentiment – some going so far as to want to leave the Union. Some are asking whether it is still possible to say with confidence, as we did in 2007, "Europe is our future".

True, the EU is in the middle of a crisis. But the situation is by no means a cause for despair – even if some see it as their role to scaremonger. Let me outline a few thoughts about how I see some of the perhaps sidelined aspects of the current difficulties and how I think we ought to approach them, in Germany, in Romania and in other EU countries. After all, it is a long time since our discourse in Europe consisted merely of a host of separate, clearly distinct national and regional debates. We also have a pan-European debate.

In Europe at the moment – both in our individual societies, to varying degrees, and in the EU as a whole – we are facing a strange and highly dangerous onslaught of negative sentiment. And I believe that nothing is more essential to counter it than rationality. But we also need to be passionate about rationality.

I don’t think it’s only political matters that are at stake. The difficulties are now also arising from varying and emotionally highly charged issues such as lifestyle and morality – differences which stand out more and more starkly the more time people spend together. These differing, indeed partly contradictory ideas and opinions about how we should coexist can be seen both within individual societies and across borders. To put it somewhat simplistically, we have the following dichotomy:

There are those who see "the others" as frankly behind the times, reactionary and all too ready to fall for the illusory promises of authoritarianism. Those others, on the other hand, see the first lot as exaggeratedly liberal, morally arrogant but pathetically weak when it comes to identity, strength and honour. But both groups see themselves as model representatives of the true Europe and its values.

On a whole range of issues, we are swept along by powerful, often polarising emotion. I’m thinking of questions like how we should deal with refugees, what the relationship is between secular and religious Europe and how we deal with high levels of debt, the banking crisis and unemployment; I’m also thinking of issues surrounding reproductive medicine, voluntary euthanasia and sexual self-determination.

As I say, that’s all somewhat simplified; reality usually comprises impure hybrids of our theoretical models. But those fundamental attitudes do have an effect in the many challenges we need to face, and they can have a powerful hold on our emotions.

It can be hard to engage in level-headed conversation about issues like that, given that they do have a moral dimension and involve value judgements. That is the case within individual societies, but it is also true with regard to the discourse within Europe.

And yet nothing is more essential than that we keep trying to return to sensible dialogue.

Let’s take a moment to look back. What is it that feeds the European idea, what feeds European culture?

What feeds that European spirit embodied, for instance, by libraries like this one and by that incomparable European invention, universities?

That spirit stands for

– the quest for knowledge

– the search for meaning in human existence

– the search for moral, philosophical or religious truth

– commitment to the rule of law

– the testing of any theory in the fire of criticism

– the vital need to differentiate between claim and fact

– argumentative dispute and objective debate

– the advance of knowledge by means of argument and counter-claim, proof and refutation

– the enhancement of knowledge brought about by consideration of unfamiliar ideas and geographically or historically distant cultures.

That spirit has been key to Europe’s cultural and political development since the first universities were founded in Bologna, Paris and Oxford. It was never quite eradicated despite brutal setbacks, and it has been and still is the greatest source of all that is positive and constructive. It is the spirit of reason, rationality, enlightenment and criticism.

There are two basic preconditions that must be met if people are to think, research and communicate with one another in that reasonable, rational and enlightened spirit. First and foremost, you need freedom – freedom to think, express and publish what you want – and, inseparable from this first requirement, you also need people to be honest and seek truth in an objective fashion.

Immanuel Kant once urged people to have the courage to use their own understanding without relying on outside guidance. But these days, some people seem to be taking that to mean we should have the courage to apply our own prejudices and not even listen to counterarguments – that we should not be afraid to present our unproven claims as facts; that we should not be ashamed to see our untested opinions as fully formed arguments.

This type of discourse, so strong on opinions but so poor on arguments, is able to spread all the more inexorably as more and more people – seemingly almost everywhere in Europe – form and hold their opinion in separate echo-chambers. Paradoxically, the internet – theoretically an unrestricted means of informing yourself and traversing any continent of knowledge imaginable – can further cement those dividing lines. The results are intellectual isolation and moral autism. Juli Zeh, a very politically minded German author, describes Unterleuten, the eponymous fictitious setting of her latest novel thus: "If I learned one thing in Unterleuten, then that is that every person inhabits their own universe in which they are right from dawn until dusk."

It’s a tricky constellation. On one side are the people who are proud of their anti-elitist stance and respond with truculent resistance to anything foreign or simply different. It’s about being against ‘them up there’ and ‘them over there’. Not infrequently, ignorance and superstition combine to enable people to see themselves as the victims of a conspiracy of malevolent powers, against whom any means of resistance are permissible.

On the other side we have that world which sees itself as entirely enlightened, whose opponents can only be suffering from cultural dyslexia or backwardness in matters of non-discrimination, pluralism and multiculturalism.

That dangerous isolation between communities with different convictions is now also affecting the discourse on Europe. It has a massive effect on our societies’ and countries’ relationships with the European Union. In a world that seems to have grown too complex to manage, a fair number of people blame the EU and its institutions and rules for the complexity and chaotic circumstances which their local, regional and national communities can no longer influence. In some communities, we are seeing a retreat into closed-off circles, sometimes even into a modern form of tribalism.

It is right that people need a home that is uncomplicated enough to give them a sense of security, a community where they can feel they belong and which also allows them a sense of pride, honour and a love of what is theirs. People don’t want to feel patronised, especially when they’ve just lived through a time of historic liberation, as people have in Romania and other countries of Central and Eastern Europe, as well as in eastern Germany.

Though it is right and proper to treasure and protect that which is our own, we must not casually put at risk everything we have indeed achieved together over the years. Let us not forget what damage was once done in Europe by nationalism. Peace enjoyed in liberty is not something we can take for granted in Europe. It did not come about by itself, and it needs to be maintained too. The primary purpose of a united Europe is not to give us cheap flights from Athens to Dublin or to get seminar credits from Bordeaux recognised at the University of Tallinn. The purpose of our united Europe is to make a lasting reality of the thing that was so elusive throughout European history: peace enjoyed in liberty.

I cannot therefore stand idly by when in movements which call themselves patriotic – but which must properly be called nationalistic – I hear massive xenophobia, old-new racism and hateful aggression being articulated vis-à-vis anything that looks and sounds like an open society, liberality and tolerance.

How absurd and destructive it would be if that one huge frontier across Europe that we happily got rid of together a quarter-century ago were now to be replaced by a whole set of new ones. That would not go well. So let’s not even imagine it.

We all know that nobody wants to be treated as second-class. Nor does any country – and quite rightly so. The fact that all EU member states have equal rights and responsibilities should therefore be something everyone regularly sees in practice, not just something written in the treaties. Nobody should be made to feel that Europe is made up of masters and apprentices. Anyone who joins the community becomes a full member, and their date of accession becomes a matter of purely historical interest.

Anyone who joins the community thereby accepts the rules and principles, the values and the conventions of that community. From the moment they join, they have an equal voice in the ongoing development of those rules. And this applies to every member too: no-one can reap the benefits of the community without also being prepared to play their part in it to the extent permitted by their means.

Considering the big issues of our time – security, climate protection, sustainable economic growth – I find it hard sometimes to fathom how some people can believe that the EU doesn’t protect our societies’ vital interests and represent them on the world stage more effectively than each member state could do on its own.

When the European project was first thought up, the talk didn’t focus on values – perhaps because they were considered a matter of course. But it was as clear to the first EU members as it is to those who joined in subsequent decades that interests need to be jointly represented and defended – and that it is to everyone’s benefit to find a way of reconciling their interests, to find compromises.

Let me in conclusion emphasise that our Union absolutely is a community of shared values too, and must remain so if it is to retain its true spirit. Nonetheless, having accepted the immutable foundations like human rights, freedom of opinion and religion, the rule of law and gender equality, there is a lot of room for the EU to take on different shapes and forms. It ought to fit right into its anti-totalitarian stance for the EU to host genuine debate about how to live our lives and shape our societies on the firm foundation of those untouchable values.

That’s something we all have to keep relearning afresh: to allow and listen to arguments that may at first seem implausible to our familiar way of thinking. We need to learn anew to activate the intellectual and moral tradition of argumentative dispute, which helped found our European culture and which I therefore wish to recall to mind here in this place.

We in 21st century Europe should be no less diverse, no less capable of engaging in debates and conflicts, and ultimately no less passionately committed to reason than the students of the newly founded universities were in the 12th century. I would rather see us somewhat more so, so that everyone in this great and beautiful Europe can look beyond their own little universe where they are right from dawn till dusk.

Thank you very much.