Many of us - even those of us most fond of science fiction movies - had never imagined that we would live through a generalized quarantine, with our families confined to their homes and the country almost paralyzed, with the exception of the minimum services that guarantee the care of basic needs for citizens. Covid-19 has infiltrated in a meandering way: first it has affected a few people, but the rate of contagion is doubling every three days. If we do not stop the pandemic, if we do not buy time, our healthcare system will collapse and we will not be able to care for the most vulnerable. To avoid this tragedy it has been necessary to approve decrees that have temporarily destroyed our way of life.

The hotels have been emptied, all the schools and most of the stores have closed, the streets are almost deserted and many companies are putting in place regulation files employment to avoid bankruptcy. We are facing a kind of unwanted social experiment: our community has become a unique laboratory, in which we can study how our habits change and what psychological, family and cultural effects these new patterns have. When the virus is defeated, we will also be able to quantify the economic impact of the pandemic on families, businesses and public accounts.

The academic world is no stranger to the crisis. Last week, 81 Spanish universities of a face-to-face nature -there are another six distance learning universities, whose activity has hardly been affected- closed our campus and sent home almost one and a half million students. We now face a triple challenge, perhaps similar to that faced by other institutions: information, digital teaching and assessment.

First of all, clear explanations must be given as quickly as possible in order to resolve the uncertainty of professionals and students. Some questions will not yet be answered: for example, it will not be possible to indicate when classes will resume or if the dates of exams will change. But we have to tell what we know and anticipate any questions that may arise. Basically, it is about the university community trusting that those of us who are at the head of each academic center are taking them into account, that we are position aware of their difficulties and that we are informing them appropriately.

The second challenge is to move from a basically face-to-face teaching to an 'online' system. Covid-19 has forced us to accelerate our digital transformation. The experience of the first days with the campus closed allows us to draw some conclusions: there are very useful free applications for the teaching 'online' and easy to use by students and teachers, which allow us to adapt to the very diverse approaches of the subjects taught; at the same time, it should be recognized that the digital experience has limits: it is not able to mimic the learning in laboratories or the multitude of informal conversations between teachers and students that happen every day in the campus.

The third challenge concerns the assessment. If the crisis is prolonged, it will be necessary to carry out these exams at a distance, with an adequate system of guarantees. In any case, those of us who teach each subject know that when we give grades we are also evaluating ourselves: we are quantifying whether we have been able to teach and motivate our students with convincing explanations and encouraging demands.

Moments of truth are unique occasions to test the strength of our character and the firmness of our convictions. In these difficult days I have perceived -and I know that the experience of many other universities is similar- that we have extraordinary students: they have offered to help in whatever is needed; they have understood that although campus is closed, the university is still open and that, therefore, it is now up to them to lead their learning process; they have accepted the need to live in uncertainty and they have understood that we cannot control all the variables.

Every crisis causes pain and this one will cause pain in many people around the world. But Covid-19 is already teaching us some lessons. There are at least four quite clear ones: global challenges remind us that there is much more that unites us than separates us, and that we advance more when we seek agreements; and among the things that unite us, solidarity, the search for the common good and concern for the most vulnerable are always a priority; on the other hand, it is important that we dedicate more funds to research, because globalization - with its undeniable advantages - makes us, at the same time, more vulnerable; and, finally, we must accelerate the digital transformation of organizations: technology changes our lives and provides extraordinary possibilities for relationships, work and communication.

In addition, a new generation of professionals with excellent scientific knowledge and a spirit of solidarity is being trained in university classrooms, who will be able to face the health, social, cultural and economic challenges of the future. This is perhaps one of the most encouraging facts detected during the pandemic.