Pessimism of the intellect, optimism of the will

Blaise Pacal famously argued that, whatever we may think about the reality of God, it is rational to believe in God for should it transpire that the big G indeed "is out there" the rewards in the afterlife for the believer would be most handsome.

It is difficult to be a confirmed pessimist or optimist. There are signs both for hope and despair. But I shall argue, along with Pascal, that we should at least have optimistic belief and act as if we are hopeful. The rewards of optimism might be vast.

There are, it must be said, interesting arguments for pessimism.

Nicholas Coperni cus is credited with providing the key early work that disproved the notion that the Earth lies at the centre of the cosmos. In this way, he helped us to ultimately move beyond Aristotelian physics, paving the way for the scientific revolution.

Ever since then we seem to have lost our sense of centrality or specialness. Things have gotten worse in that respect.

We know that our galaxy is not unique, that there are other galaxies. We know that there are clusters of galaxies. We know that our local cluster of galaxies is not so special for there are also galaxy super-clusters. We are now even finding other planetary systems.

We know that, courtesy of modern cosmology, based on Einstein's theory of General Relativity, that there is no unique vantage point to the universe; no place in the universe is "special." The universe is homogenous and isotropic. It might well be the case, indeed almost surely so, that there exists more to the physical world beyond the observable universe.

This cutting down to size of humanity through the use of increasing scale we call "the Copernican Principle." The Copernican Principle, and its at first brush seemingly contradictory cousin, the Anthropic Principle, is attracting increasing controversy in theoretical physics that has seen physicists question the very nature of science, much less scientific progress.

The most fashionable theory in physics these days, string theory or superstring theory or M-theory, seems to require the existence of many universes known as "the landscape" or "the multiverse." Though string theory holds the promise of being a "theory of everything," and so the ultimate expression of progress in human knowledge, it actually has many "solutions" that describe different worlds.

Each would have its own laws of physics. We happen to live in a universe where the laws of physics are conducive to the evolution of life and so we ought not be in the least bit surprised, given our existence as observers, that the laws of physics here take the form in which they do. The point is that they could be otherwise albeit not here. This is a curious way of combining the Copernican and Anthropic principles. The theory of everything becomes a theory of anything. Though more could be said the time has arrived to bite the tongue.

This tale is not unrelated to our topic. For it is argued, with the utmost justification, that such considerations demonstrate that fundamental physics has gone backwards since the early 1980s.

The parallel between the dominance of string theory in physics and the neoclassical dominance of economic theory is striking in this regard. Even some of the main mathematical considerations, such as the use of topology in string theory and general equilibrium theory, are shared between them. Alas, time to again bite the tongue.