In her previous book, "Pythagoras's Trousers" (1997),
Wertheim tried to prove that 1. Western physics was created within the framework and the infrastructure of the Christian religion; and 2. Western physics was inherently male because physics was grounded in Christian institutions from which women were banned.
This follow-up is a much more interesting book, whose premise is
that the concept of the self is largely shaped by the concept of space,
and the concept of space has been transformed in the West by both the arts
and the science.
Wertheim starts with Dante, whose "Comedy" well represents the separation of Heaven and Earth (spiritual and physical space) that was commonplace in Christian mythology. She then moves on to his contemporary and compatriot Giotto, who emphasized physical space in his Padova/Padua frescoes (Cappella degli Scrovegni, completed in 1305), and on to the Assisi basilica, that boasts similar "realistic" frescoes. Physical space was being reimagined also in books written by philosophers and proto-scientists such as Roger Bacon's 840-page "Opus Majus" (1267), Hasdai Crescas' "The Light of the Lord" (14xx) and Nicholas Cusano's "De Docta Ignorantia" (1440).
The perspective painters of the Italian Renaissance, starting with Giotto, were influential in redefining physical space because, as Samuel Edgerton wrote in "The Heritage of Giotto's Geometry" (1991), and later in "The Mirror, the Window, and the Telescope" (2009): once people started seeing space in a different way they also started thinking about space in a different way. Wertheim argues that Galileo's "continuous homogeneous three-dimensional void" (the so-called "Euclidian space") was the natural consequence of the background used by perspective painters. Wertheim sees Galileo's universe as being made of matter and void. Aristotle had claimed that the void is impossible. Therefore here was a fundamental defeat of Aristotelian thinking.
The next step in redefining the concept of space was to unite celestial and terrestrial space. This process was started when Galileo used a telescope to look at the Moon, but, again, the separation between the two had already been indirectly challenged, in Wertheim's opinion, by Raffaello/ Raphael in his painting "La Disputa" (trivia: Wertheim translates the name of the painter into English but then leaves the title of the painting in Italian). This was the first painting to paint both Heaven and Earth in the same manner. Copernicus, Kepler and Newton simply completed this unification of celestial and terrestrial spaces. Once conceived as a planet orbiting around the Sun in empty space, the Earth became a celestial object itself.
Newton was a very religious man, and reserved to God the job of creating the universe and setting it in motion. But his physics didn't need the hand of god once the universe started moving, and his physics didn't have a space for the soul: the celestial space was now simply an extension of terrestrial space, obeying the same laws.
The belief that the universe was static, created once and forever, was so strong that Einstein himself believed it and tweaked his famous equations to produce a static universe. Edwin Hubble's observation that the universe is expanding changed all that. (Wertheim points out that Kant had already been unhappy with the idea of a static universe in his book "Universal Natural History" of 1775). Einstein's relativity, that actually predicted the expansion of the universe, totally destroyed the traditional concept of space, and introduced the idea that space is an actor in the history of the universe (matter warps space, which in turn determines the evolution of matter). But Wertheim is more interested in the "spiritual" consequence of cosmology: the Big Bang denies God the role of creator, and the cosmological principle (that every place in the universe is equally important or un-important) denies us a direction. Dante's journey had a clear direction: from hell to paradise. But we have "no place to go".
Wertheim's breathtaking survey of the evolution of the concept of space ends, basically, with existentialism angst. Now we have mapped the universe and we know how it became what it is, but, in the process, we have been revealed powerless to even explore it, let alone to find a direction in which to explore it.
Borrowing from Linda Henderson's "The Fourth Dimension and Non-Euclidean Geometry in Modern Art" (1983), Wertheim talks about the artists and writers who "discovered" the extra dimension before Einstein: Edwin Abbott in the novel "Flatland" (1884), HG Wells in the novel "The Time Machine" (1895), Gaston Pawlowski in the story "Voyage au Pays de la Quatrieme Dimension/ Journey to the Land of the Fourth Dimension" (1912), Marcel Duchamp in the collage "La Mariee Mise a Nu par ses Celibataires, Meme/ The Bride Stripped Bare by Her Bachelors, Even" (1915), etc. Mathematicians had been working on non-Euclidean geometries, most famously Carl-Friedrich Gauss and Nikolai Lobachevsky. Wertheim borrows from Michio Kaku's "Hyperspace" (1994) to credit Bernhard Riemann with more than his version of non-Euclidean geometry (1854): according to Kaku, Riemann conceived gravity as an illusory force that was in reality due to distortions of three-dimensional space, which is pretty much the essence of Einstein's general relativity (1915). Einstein finally worked out the precise relationship between "gravitational force" and spacetime: one is the visible effect of the invisible action of the other. In 1919 Theodr Kaluza had the idea to continue Einstein's program: if Einstein's equations in four dimensions explained gravitation, Kaluza's equations in five dimension explained both gravitation and electromagnetism (they include as special cases both Einstein's and Maxwell's equations). Space (actually spacetime) was slowly becoming the only reality of physics. In fact, later string theory imagined that all matter is nothing but tiny perturbations in a multi-dimensional space. Hence physical space, whose story begins with Giotto, ended up becoming the protagonist of physics' world picture. If Newton had matter and forces playing out in space, post-Einstein physics has matter and forces arising as by-products of space. Wertheim views the physicists who search for the "theory of everything" as focused on explaining everything out of space, an approach that basically turns space into the Judaistic-Christian God. She objects that spacetime geometry cannot be the totality of reality (although she doesn't quite explain what cannot be explained from spacetime geometry). The space of physics is therefor ineffective to take the place of heavenly paradise.
Luckily, the 20th century also produced cyberspace, and this one works better for creating mythologies of the afterlife. Cyberspace restores the medieval dualism: there is a physical space and there is a non-physical space. Cyberspace also happens to be expanding very rapidly, just like physical space. The Big Bang of cyberspace took place in October 1969 when the first two nodes of the Arpanet (later Internet) were connected. Cyberspace is where the self can construct itself. Wertheim points out that Dante's "Comedy" today would be a MUD, a virtual world in cyberspace. Wertheim likes the idea that cyberspace has given us an immaterial space because, first and foremost, we (the "i") are immaterial.
The popularity of Hans Moravec's book "Mind Children", a book that hints at the possibility of resurrection and immortality in cyberspace, is a sign that the highly technological society that we have created needs a new religion, and luckily cyberspace provides a viable alternative to physical space. Wertheim finds similarities between the book of Revelation and cyberpunk fiction by Gibson and Vinge, while quoting Jeffrey Fisher's article "The Postmodern Paradiso" (1997) that found similarities between Christian mythology and cyberspace utopia. Wertheim finds an undercurrent of Pythagorean mysticism in the language of cyberspace heroes.
The last chapter was outdated already in 1999 and sounds very outdated almost 20 years later but of course that's easy to say. A lot of things changed. One point that she makes towards the end is, however, interesting even today. We assume that the Internet-based technological revolution happened "just because", but she asks whether it happened when it happened because society was "asking" for a new kind of space beyond the purely physical one. Could the Internet revolution have happened earlier? Did it have to happen now? Could it be that the Western society was looking for something that the hyper-materialistic modern world was not providing and enthusiastically turned the Internet into that "something" but could have as well turned some other technology into that "something"?
Wertheim evokes Umberto Eco's opinion that the USA of the 1990s resembles the last decades of the Roman Empire (a totally silly comparison in my opinion, given that the Soviet Union has just collapsed and the USA is now the only superpower, so powerful over the rest of the world as no other country has ever been) and then she finds a similarity between the way Rome adopted a new religion, Christianity, and the USA is adopting a new religion, the religion of cyberspace (soon to become the religion of the "Singularity"). More credibly, she argues that the progression away from the spiritual space of the Christian world due to the scientific and industrial revolutions has made humans masters of the physical space but deprived them of any spiritual space.