Filippo Brunelleschi, gazing up at his most famous creation, the dome of Santa Maria del Fiore, the Duomo of Florence. This bald, average-looking Florentine is one of the key figures of the Renaissance, developing concepts in architecture, engineering and sculpture that helped define the western world for centuries to come. He discovered perspective, for crying out loud - it doesn't get more fundamental than that.

And here we were, not an hour after taking his picture, standing atop that dome and looking across the city of Florence as if it were still the 15th century.

Ah, the Renaissance! That confluence of new ideas and re-discovered Roman and Greek enlightenment. A continent had survived multiple plagues, countless wars, and general ignorance for centuries. It was waking up now, and seeing itself in a whole new light. Art, architecture, engineering and philosophy, all were blossoming like teenagers. And like adolescents, they were a giddy jumble of excitement, fear, daring, ignorance and sex.

Think I exaggerate? Take a look at the inside of Brunelleschi's dome:

At the bottom levels of this massive fresco, sinners lament as they are tortured in terribly imaginative ways by terribly scary creatures. A little higher up and you see those who are escaping the torment, trying to help those who are still in danger. Further up still you see the rapturous, on their way to heaven to meet their king, who sits at the top, exuding eternal peace and glory.

Talk about compelling. Who would you want to be - the poor guy getting flogged by the toad-man, or the one being pulled to the sky by a gaggle of naked Florentine angels? Makes even the atheistically minded stop and think for a moment.

It is also a great example of everything that was happening during the Renaissance. The mix of fantastical religious figures with very real human forms. The use of perspective so that heaven really looks like it is heaven and hell looks way too close for comfort. The design and engineering that enabled this spectacular structure to be built in the first place. All of it a living textbook on the tipping point from the Dark Ages to now.

Walking through Florence I couldn't help but imagine myself there during its heyday, with the buzz that comes from being a part of history as it is being written. Watching these new buildings rise up, seeing new works of art being unveiled, and hearing new thoughts about the human potential.

How would I have participated? Would I have embraced these new ideas? Would I have contributed, engaging whatever talents I had to better my society and the ones that came after? Or would I have let myself be left behind, staying forever with the toad-men?