Socrates
So what does all this investigation tell us about the underlying nature of the cosmos we find ourselves in?
Actually, very little.
As a teenager, I spent a lot of time thinking about the meaning of life, as many do, and what we can really be certain of. At that time I wrote some plays in the style of “radio plays” and some of my friends acted them out to be circulated on tape.
One of those plays was called "A voyage to infinity".
This was long before films like “The Matrix” and long before phrases such as “virtual reality” and “artificial intelligence” had even been coined. I had not heard of Descartes and his “evil demon” but the possibility that the information we received through our senses did not portray the real world but came from some other source had occurred to me.
In the play, some travellers manage to discover that all of us were simulations in large computers, Matrix style, and what we thought was the real external world was an illusion. The actual real world which they found was very different to what they had perceived.
I found this possibility deeply unsettling. The ground we stand on is far less certain than we think.
Firstly we assume that our senses tell us the truth. We rely on our senses for everything we know but we cannot tell where these sights and sounds are coming from nor know if they are giving us a true picture of the external world.
Secondly we assume that the laws of Nature that scientists discover operate not only at the time and place where the scientists perform the experiments, but everywhere and at all times. This is by no means self-
Although there are some people who maintain that the scientific method is objective and does not rely on faith, science is built upon these unprovable foundations.
Some would reply that these presuppositions are proved true by the success and predictive power of science. However it is very possible to get the right answer for the wrong reasons. For instance, Tycho Brahe’s model of the Solar System was successful in predicting the motion of planets but the model was later shown not to be valid more generally.
Let’s look a bit more closely at the assumptions.
This has been tested by a number of well known thought experiments.
Rene Descartes famously attempted to find out what it was possible to be certain of. He started with the knowledge that he existed, based on the fact that if he was thinking then there must be a thinker.
To illustrate how little we can know, he imagined the possibility of an “evil demon” who had taken a brain and connected all the inputs and outputs to some sort of data source. Others have spoken of a “brain in a vat” to mean the same thing and the film “The Matrix” gives a dramatised version. There is no way that we could tell whether we were in this unfortunate condition or whether we really were seeing things as they are.
Descartes didn’t get much further without getting embroiled in circular arguments.
Others have tried to prove that the world we perceive is the “real” world, such as Bertrand Russell, Hilary Putnam, Henry Moore and others. I find none of their arguments convincing and would not want to put any faith in them.
David Chalmers takes the view, which I share, that we cannot know whether we are in a simulation or not but that this makes no practical difference to us.
Whether the underlying reality is based on atoms, a multi-
Without suggesting that we really are actually living in a virtual Universe, what this shows is that it is not hard to imagine that there can be aspects of reality to which we simply are unable to access or even be aware of. Not only can we not know whether our Universe is “actual” or has been constructed by some agent using an actual Universe as the substrate, we cannot find out anything about the origin of our Universe at all, neither how nor why it came to exist or the whether an agent created it.
Based on experiments done on Earth by a number of scientists over a minuscule amount of time compared with the lifetime of the Universe, Laws of Nature are proposed and are assumed to be true for all space and all time. There is no way to know if this is true.
The only way we could find out such things is if the Creator communicated it to us. The information channel has to be opened from the outside.
In particular, this assumption implicitly excludes what could be called the “miraculous” in which there is an influence from outside of Nature. While such a situation is usually considered to be impossible, there is no way of proving it. Consider again the analogy of a virtual Universe where the “Laws of Nature” are set by the programmer who is fully able to intervene in special cases.
Those who assert that physics is a closed system and can explain everything deny that possibility but there is no logical reason to do so.
This physicalist belief works well for much of what we investigate but one of the things it is it is incapable of accounting for is conscious experience despite the huge efforts trying to make it do so.