Life is full of illusions. So full, in fact, that life itself may be an illusion. Why is it that some years in our earthly existence seem so much longer than others? Why is it that some people see life as a gloriously positive experience and others bemoan the lugubriousness of reality? Why is that the smallest problems seem huge and the largest ones mere specks?

Happiness is the biggest illusion, of course, and my life has been somewhat tortured to say the least. I never found my beloved or experienced pure joy. I did not have the suave manners and erotic attractions of my contemporary Bernini. I envied him his seductive behaviour and his indubitable talent. However, I am one thing which Gian Lorenzo is not: an architect. He is a sculptor who became a part-time architect while I was born and remain an architect. He based his design on the human body while I worked mine out using geometrical forms. On one thing, however, we did collaborate closely and that was the baldachin that covers the high altar of Saint Peters. At least we did agree on that one. I just wish we could have done more friendly collaborations as so much was happening to add to the golden baroque splendour of my seventeenth century Rome.

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I also managed to participate with Bernini in the staircases we built for Cardinal Barberini’s palace. Here is my rival’s effort:

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But I think my own solution is rather more adventurous:

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Tantalisingly at other times I had my commissions taken over. That was the case with my church of Sant’ Agnese in Agone in Piazza Navona

and so many of my original designs such as Sant’ Andrea della Fratte and San Filippo Neri were maliciously altered. These spurnings and rejections added to my gloomy attitude and even made me think that everyone was against me. Unfortunately, too, my temper often got the better of me: on one occasion, for instance, I almost kicked to death a labourer working on one of my projects because I thought he was spoiling my building material.

My big problem was what would be described in your age as ‘chronic depression’. In ours it was called ‘melancholia’ and we had no Valium pills to take then. Combined with my irascible temper it ruined my life and, indeed, almost got me to take it. I was obsessed by suicide to the point when on a particularly hot summer’s night, unable to sleep and with mosquitos attacking me, I found a sword and fell upon it. Unsuccessfully, however. A neighbour found me in a pool of blood and called the doctor in the nick of time.

There were spells when, feeling threatened by an exterminating angel, I felt unable to step outside my house for weeks. My old servant was so worried that I would starve myself to death; I was apprehensive that they might steal my architectural designs and so one evening I burnt them all.

I never recovered from my sword wound and died not long afterwards. Miraculously, as if God had finally taken pity on me I regained my lucidity of mind, asked forgiveness from the Almighty Father and received my last sacraments. I requested to be buried anonymously in the grave of my teacher and friend, Maderno who was instrumental in changing the design of St Peter’s Basilica from a Greek to a Latin cross.

Anyway, as I already said, it looks to me that life is one big illusion. Not a ‘con’ mind you but a supernatural illusion – a sempiternal cosmic joke if you like where one is led astray by preconceived hallucinations and habitual visions. I placed my own illusions – sometimes they could be better described as disillusions – in my buildings; making smallness become greatness, as in my church San Carlo alle Quattro Fontane (now you wouldn’t think that this grand little church could fit into one of the central piers of Saint Peter’s basilica would you?)

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or by emulating academic mathematicians at their own game as in my church of Sant’ Ivo built for la Sapienza, Rome’s university and based on measurements derived from the then new branch of Calculus.

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Like that English architect, Sir Christopher Wren, I was often challenged by the most awkward sites. How to fit in a building on these sites and make them look full of presence was my constant puzzling delight.

One of the most fun things I did is that galleria you have seen today at the palazzo originally designed by Bartolomeo Baronino but which I modified to the latest taste for Cardinal Bernardino Spada.

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You pass into the palace’s courtyard and on your left you see the gallery with a perspective that makes you feel you are going into next door’s garden. Or are you? Of course not! It’s just an illusion.

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You’d think that the arcade is around thirty metres long, while in reality it is less than nine. With the help of my mathematician friend Father Giovanni Maria da Bitonto I created a deception where planes converge into a single vanishing point; while the ceiling descends from top to bottom, the mosaic floor rises. At its end there is a statue of a warrior from the Roman era. The sculpture seems full size but is only a yard high and, as for the width of the arch before it – well I’ll get you to work it out with your pocket calculator!

The gallery is also the result of the Cardinal’s interest in games of perspective. Spada clearly attributed to this gallery the meaning of moral deception and the illusion of earthly magnitude. We think we are so powerful and almighty but we are mere puny mortals. Our greatness is a mere illusion just like that statue at the end of my gallery.

By the way, if you are film-lovers (your own contemporary creators of illusions) Sorrentino’s Oscar-winning film ‘La Grande Bellezza’ has the magnificent Borrominian perspective set in one of its scenes.

PS Don’t forget to visit the lovely collection of paintings in the Palace’s first floor.

They include masterpieces by that once rare phenomenon, a female artist, Artemisia Gentileschi who I had the delight of meeting but was never able to capture the love I had wished from her.

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I am so glad that the lovely golden tables I remember in the palazzo are being restored too. One has already been finished – two months’ work – and the other is on its way to regaining its original lustre.

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Don’t worry about the profusion of carabinieri, grey suited men and large black saloon cars around the Palazzo. Cardinal Spada’s city mansion does, in fact, house Italy’s supreme administrative and judicial body the ‘Consiglio di Stato’ (the state council) which has jurisdiction on acts of all administrative authorities and consists of the President, eighteen section presidents and ninety two councillors of State. I think the cardinal would be delighted to know how important his elegant palazzo has become. I just hope that the council’s policies and results won’t be counted as other illusions to be set along with my little-large galleria…

PS Don’t feel sorry for me: I know I’m now getting my due in architectural history by the academic writers at long last…

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