Equality and freedom of expression are fundamental democratic values. Combining them means that everyone has an equal right to freedom of expression. But while there is constant talk of the right to freedom of expression, the opportunity to be heard is quite a different matter. In fact, the mass media, for example, are shaped by just a fewpeople: social media tend to circulate popular content, and focus on user preferences.

The best opportunity to reach a broad audience is therefore the city's public spaces. Here, the right to demonstrate or distribute leaflets - at least in democracies - is guaranteed. But these are usually only temporary, quickly forgotten actions. What shapes our perception much more are the permanent elements of the urban landscape: the endless rows of shop windows and ubiquitous advertising that leave no doubt that consumption is supposed to play a decisive role in our lives; election campaigns that confirm us in the view that social participation consists of choosing from among the existing political options; commissioned sculptures and murals that teach us what “real art” is. Even the clean house walls convey a message. They tell us that public space is ours to use but not to shape.

The same work may be considered art in a museum but vandalism on a house wall

But what if we think beyond the usual notion of legal order? What if it was not a small group of politicians, property owners and companies that decided how our common space should be designed, but all of us? What if property rights no longer extended into public space, but were limited to internal space? After all, the official urban landscape is meeting with resistance. Graffiti, in particular, breaks through its dominant narratives and claims its own right to the city. What if these private contributions to urban design were legal and not punished by the legal system?

This would give everyone a truly equal right to express themselves: a right to help shape the city and thus to share their own world view and perceive that of others. This would promote understanding between social groups. As the Black Lives Matter movement recently showed, it sometimes still takes far too long for social injustices to be perceived by the general public. In a city full of expression, this might be different.

We imagine a city made of collages, a city that creates space for the opinions and artistic expressions of its inhabitants. After a period of acclimatisation, such a colourful urban landscape wouldn't appear untidy or dirty to us. After all, dirt is something that is in the wrong place. Even today, the same work can be perceived as art in a museum and as vandalism on a house wall. But if we were to expect to find pictures and writing on house walls as well, we would soon welcome them rather than reject them. The art world would also benefit. For today it is characterised by the dominance of the market and the art experts. There is little room for truly free artistic expression. Yet this aspect of art is particularly valuable, because it can question existing aesthetic norms.

But what could a first concrete step towards a right to help shape one's own city? We are currently planning a project in Berlin on this question. The idea is to give all citizens the chance to present their own contributions on trains and other means of transport. These contributions can take any form - for example as a picture, photo, joke, poem or saying. This would make Berlin the first city in the world to enable individuals who are neither famous nor rich convey their messages to all fellow citizens in a visible and eye-catching way.