Renzo Piano, on his interview in http://www.dezeen.com/2012/05/18/interview-renzo-piano-on-the-shard/
But I think you are touching something very important, which is the discussion about style, the griffe, the recognisable gesture. I believe this is part of the star system of architects but its not a good story for architecture because it doesn’t celebrate architecture but celebrates the architects. I think in the end is not good for architecture because in the end it limits the freedom. You as an architect – let’s assume you have a certain success; you are always pushed to repeat yourself. It’s not just true for architects; it’s also true for painters, writers, film makers. If you do something, people will ask you to do it again. But this is not a good story; this is a lack of freedom.
Everybody talks about a lack of freedom but probably the most difficult freedom to keep is not from other people but from yourself. Freedom from other people is quite easy; if you have a tough group of people working together as we are – honestly, we defend our freedom quite well – but the most dangerous freedom to defend is the one with yourself. Because you get used, you become self-referential, because things go well. So you fall in the big trap, which is the one of recognisable signature. The idea that you do things this way. So immediately people say that is Pierre Cardin, Hermes or whatever. I’m not saying this to be a moralist; I hate this idea of a repetitive gesture or a self-referential attitude; I hate this idea of being trapped by the need to promote your griffe – your label – but at the same time I love the idea of coherence. I love the idea that an architect has their own language. We have to constantly fight against the temptation to repeat yourself.
So there are many many things here that are the invisible parts of architecture. It’s a bit like an iceberg. The invisible part is what I call the social vision for a city, the context and things like that. It’s very strongly there. Unless you do this, architecture becomes very quickly an academic exercise; a formal exercise.