Sunday, June 12, 2011

Reports of the death of philosophy are exaggerated

In his latest book, “The Grand Design”, the Cambridge professor and author, Stephen Hawking, has declared that “…philosophy is dead”. That seems a bit, um, final, particularly as some of his own work, especially that related to so-called black holes, those regions of space where matter is believed to be so densely packed together that the gravitational forces thus generated will not even allow light to escape from them, is some way from attaining the status of a theory that can be tested by experiment. Hawking originally held that all information about black holes was lost due to their extreme density, but in 2004 he changed his mind and began to argue that certain information could, in fact, escape from them.

In other words, at best black holes are imperfectly understood. They are postulated to exist towards the macro, or very large, end of natural phenomena. At the other extreme, at the micro level, when consideration is given to how atoms are held together, scientists are really little better off. The classic model of the atom, which those of us who did science subjects at school were presented with, has a nucleus which is surrounded by one or more electrons kind of rotating around it, in something like the manner of the planets orbiting the Sun. But this runs into serious difficulties when it is realised that the electromagnetic forces that govern the behaviour of the components of any atom are nothing like the gravitational forces that keep the Solar System intact.

As has been pointed out by David Deutsch in his book “The Beginning of Infinity”, this explanation could not work at all because “…even gravitationally bound objects are, in fact, spiralling towards each other, [but on a time scale that is measured in eons], while the corresponding electromagnetic process [the mutual attraction of the positively charged nucleus with the negatively charged electron] would result in the destruction of all atoms in a fraction of a second”.

According to Deutsch, “…atoms could not exist at all according to classical physics”.

So how are they explained? Not in anything like a definitive manner, it turns out. Deutsch has put forward an hypothesis that is based on the latest work in quantum physics. This involves the existence of a multiverse, which is a collection of parallel universes, but he is careful to acknowledge at the start of his book that this explanation is far from enjoying universal acceptance among practitioners in the field. In fact it is controversial.

To me, all of this indicates that, in terms of things such as black holes and an explanation for the true formation of atoms, thinkers are really only at the stage where they can come up with hypotheses for testing against reality, to be modified or rejected outright if the evidence eventually does not allow them to be sustained, all of which is in accordance with the scientific method.

Which is exactly what the philosophers of antiquity did. When Plato and his colleagues put forward the idea that all matter was made up of four elements – air, fire, earth and water, they were simply starting the process, using the knowledge and methods of observation that were to hand, that was modified and added to by others in a cumulative manner throughout scientific history. This includes Ernest Rutherford, when he came up with his planetary model of the atom described above, in 1911.

On this basis, Stephen Hawking, far from being able to support his assertion about the death of philosophy, is himself one of the foremost modern proponents of it. In other words, science and philosophy are inextricably linked, and have always been so. In fact, in Isaac Newton’s day, when he was musing about the nature of gravitation by, reputedly, reflecting on the convergence of a falling apple with the top of his head, and co-inventing the branch of mathematics known as the calculus, and working out his laws of motion, among other things (one of which was attempting to find the formula that would turn base metal into gold), the work he did was referred to as “natural philosophy”. This later came to be known as physics.

No comments: