I'm still making my way through a thick, serious, thoughtful, well-written science/philosophy book, "The Singular Universe and the Reality of Time."
The authors, Roberto Mangabeira Unger and Lee Smolin, wrote different parts of the book. I've just started reading Smolin's chapters. He's a philosophically minded physicist, while Unger is a scientifically minded philosopher.
A couple of topics particularly interested me in Smolin's opening Cosmology in Crisis chapter.
First, the notion of naturalism -- which he says comes in two flavors, timeless and temporal. Smolin defines naturalism this way:
Naturalism is the view that all that exists is the natural world that is perceived with, but exists independently of, our senses or tools which extend them; naturalists also hold that science is the most reliable route to knowledge about nature.
He adds that "my definition doesn't claim that science is the only path to knowledge, nor does it call on nor require that there be a scientific method."
A central theme of this book is that time is the most real thing in the universe, a view that is at odds with the basic philosophical perspective of a majority of modern scientists (for example, in relativity theory time usually is considered a "fourth dimension," which puts it in the realm of space).
Here's how Smolin describes two ways of looking upon naturalism. This was a fresh insight for me, sort of a merging of science and spirituality.
One way to frame the project this book advances is to emphasize how fundamentally our conception of nature is shaped by our understanding of time. The notion of a law of nature is much changed if one thinks that the present moment and its passage are real or are illusions hiding a timeless reality.
If one holds the latter view, then laws are part of the timeless substance of nature, whereas on the former view this is impossible, as nothing can exist outside of time. Even the creed of naturalism, i.e. that the natural world is all that exists, can mean two very different things, depending on whether you think existence is only real in each moment or only applies to timeless entities such as the history of the universe taken as one.
To make this distinction clear I propose to call the view we set out in this book temporal naturalism, and to distinguish it from its opposite, timeless naturalism.
Temporal naturalism holds that all that is real (i.e. the natural world) is real at a moment of time, which is one of a succession of moments. The future is not real and there are no facts of the matter about it. The past consists of events or moments which have been real, and there is evidence of such moments in presently observable facts such as fossils, structures, records, etc. Hence there are statements about the past that can have truth values, even if they refer to nothing presently real.
Timeless naturalism, on the other hand, holds that the experience of moments of time and their passage or flow are illusions. What really exists is the entire history of the universe taken as a timeless whole. Now is as subjective as here and both are descriptions of the perspective of an individual observer. There are, similarly, no objective facts of the matter corresponding to distinctions between past, present, and future.
There's a lot to mentally digest here. Just these two contrasting sentences encapsulate a heck of a lot of scientific and spiritual/religious/mystical philosophizing.
(1) Temporal naturalism holds that all that is real (i.e. the natural world) is real at a moment of time, which is one of a succession of moments.
(2) Timeless naturalism, on the other hand, holds that the experience of moments of time and their passage or flow are illusions.
I'm reminded of the similarly different cosmic perspectives of Buddhism/Zen, which is in line with (1), and Hinduism/Vedanta, which is in line with (2).
Many spiritual people subscribe to a Be Here Now outlook. Others, to a Flee This Illusion viewpoint.
For many years, thirty-five or so, I believed that it was possible to achieve a change in consciousness through meditation and other means that led to an experience of a timeless transcendent reality. This wasn't naturalism, of course, but supernaturalism.
It bore a lot of resemblance, though, to Smolin's timeless naturalism -- with a "super" added to the last word.
Smolin spends the rest of his chapters arguing for the scientific relevancy of temporal naturalism, as Unger did in a more philosophical manner in the first part of their book.
Emotionally and intuitively, I can tell that I'm already on board with temporal naturalism. It provides answers to some questions that have perplexed me. Like, where are the laws of nature? And why is there something rather than nothing?
More accurately, temporal naturalism dissolves such questions.
From what I've read so far, Unger and Smolin say that the laws of nature aren't separate from natural phenomena. They appear to be unchanging and outside the bounds of time, but this is only because of the nature of our cooled-down world.
At the moment of the big bang, and in other extreme parts of the present-day universe (like black holes), the laws of nature were/are different from how we typically see them now. Unger writes:
In these very early moments of the history of the universe, as the earlier discussions of the second cosmological fallacy suggested, causal connections may not have assumed law-like form and the division of nature into enduring natural kinds may not yet have taken shape.
More simply put, Unger and Smolin direct our attention to the now of the present moment which is, as noted in the passage quoted above, all that is real.
Meaning, in temporal naturalism there is no search for the eternal, the infinite, timeless laws of existence beyond what exists in this one and only natural world.
There is a search of a different kind: for an understanding of how the universe is put together and functions now, which entails a concomitant understanding of the causal connections between previous states of nature and what is evident now.
Makes sense to me. Both scientifically and as a guide to everyday life.