Universes

by John A. Leslie

Universes discusses the alleged evidence of fine tuning; mechanisms by which a varied set of Universes might be generated, and whether belief in God could be preferable to accepting universes in vast numbers.

Genres: Philosophy, Science

240 pages, Paperback

First published November 30, 1989

About the author

John Andrew Leslie (born August 2, 1940) is a Canadian philosopher. He was educated at Wadham College, Oxford, earning his B.A. in English Literature in 1962 and his M.Litt. in Classics in 1968. He is currently Professor emeritus at the University of Guelph, in Ontario, Canada.

Reviews

[Szplug · Rating 4 out of 5]

I've got problems with Leslie's anthropic cosmological perspective which posits an argument from design based upon perceived evidence of fine tuning, but they are difficult to articulate: I'm intuiting that he's not presented the full and accurate picture, especially when it comes to his astronomically large numbers which can approach the quantitative event horizon of 10^1,000,000; that his analogies, while persuasive and pungent, somehow fail to present actuality in the correct correspondence or perspective. Perhaps the easiest way to put it might simply be that as far as we've come in our understanding of both the makeup of our cosmos and the physical laws with which it is governed, we're yet neophytes: we cannot even say, with any degree of certainty, how old the universe is, or its ultimate spatial immensity (with some scientists claiming it stretches up to 10^25 times further than we can see), or how many dimensions are at play—which means that it is likely still much too early for us to feel we need formulate a designer to account for what we believe to be a multitude of fine-tuning, particularly within the interplay of the Four Fundamental Forces and that of fields and masses. Yet with that said, it's a mightily impressive argument he's fashioned, philosophically sound and rigorous in its understanding of physics—or at least as far as I can discern from a layman's perspective—and what really resonated with me was how he seized the familiar Multiple Worlds argument from the metaphysical realm of abstract speculation and endowed it with a logical necessity and reality for those who would make use of its statistical properties. Well-wrought and well-presented, and producing a bounty of cosmological food for thought—in toto mind-stirring in the best of ways, if the incomprehensible vastness of our universe, and the similarly unfathomable degree of delicate balance it required in order to evolve a consciousness that could behold that minute perfection, invokes your curiosity and/or puzzlement to no end. Interestingly enough, the God whom Leslie espies manning the helm is not one recognizable in either of the two Biblical Testaments, but rather a Neoplatonic figure:

God (not necessarily the God of Christianity or of any other religion) is best described as a creative ethical requirement that the universe exist or (which is just to phrase things differently) that God is the world’s Power of Being, i.e., its creative ethical requiredness.

With that said, Leslie's Monism doesn't seem to offer up much in the way of answers, but rather a nebulous comfort that our universe and its physical laws are purposive, though to what end—apart from its ontic facticity and demiurgic potentiality—remains unknowable. Indeed, as I've never found the Problem of Evil particularly problematic in regard to God's existence, the answers Leslie provides strike me as reasonable without actually imparting much beyond a strengthening fiber for his argumentative framework. IOW, it's a fantastically fascinating postulation, but rather moot in light of the ignorance we ultimately remain in when the interstellar dust has settled. Nonetheless, explorations of and expositions upon our corpuscular presence within the unbounded environs of the universe never fail to stir me, and thus four-and-a-half enthusiastic stars, rounded down solely due to the pervasively repetitive nature of the whole—notwithstanding its unavoidability for the case Leslie deems it requisite to build, it serves as a slight drag against the ideational thrust of the authorial engines.

[Tom · Rating 1 out of 5]

I'm not sure I should really count this as "read." I skipped a lot and skimmed a lot. This is the most tedious book of mental gymnastics I think I've ever read. Has some good points, and is a foundational text for some people regarding cosmological design arguments. But sheesh. Guy needed an editor.

[Joseph Yue · Rating 2 out of 5]

Once upon a time this used to be an influential book in discussions around cosmic fine-tuning and the anthropic principle, but as of 2025 it is fairly outdated, especially in its content regarding cosmology. One may of course suggest that all we need to do is to keep updating our philosophical speculations according to the freshest, hottest, rock-n-roll-est scientific theory, but when was the last time all the scientists agreed with each other on a foundational issue like the early universe or the origin of life? Is scientific inquiry even adequate in principle to offer answers to such questions? So, this is the natural consequence of philosophers trying to "get on with the times" - they can't (for most of them are not professional scientists), and as a result they always fall behind the times and become embarrassingly obsolete. Perhaps instead of talking about cosmic fine-tuning and big bang with half-baked knowledge, it would be much better to return to the timeless concepts underlying these scientific theories, such as teleology and pure act, especially when such conceptual tools are returning to contemporary science as well.

[Steven H · Rating 5 out of 5]

A CANADIAN PHILOSOPHER CONCLUDES THAT BOTH GOD, AND "MANY VARIED UNIVERSES" ARE POSSIBLE

John Andrew Leslie (born 1940) is a Canadian philosopher, who is currently Professor emeritus at the University of Guelph, in Ontario, Canada. He has written other books such as 'The Mystery of Existence: Why Is There Anything At All,' 'Immortality Defended,' 'Infinite Minds: A Philosophical Cosmology,' etc.

He wrote in the first chapter of this 1989 book, "Rightly or wrongly, this book shows no interest in the kind of God who designs the structures of individual organisms... or who interferes with Nature's day-to-day operations. If God exists then ... there are only two ways which will be considered in these pages. First, he makes the universe obey a particular set of laws... Second, he creates its initial state in such-and-such a fashion." (Pg. 2)

He makes an argument, "Let us agree that in God's absence our births could only be a matter of tremendous luck. Let it be supposed that if ... Nature's four main forces had occurred slightly differently in our universe than living beings could never have evolved in it... So what? The hypothesis of many universes shows how it could be likely that SOME set of living beings should have the luck of being born. While they would be extremely lucky, their luck would not be unbelievably amazing." (Pg. 12) He continues, "the existence of countless universes may well have made it virtually sure that at least one universe would become 'ours' to living beings..." (Pg. 15)

He states, "Why believe in other universes when we cannot know of them directly? It could only be because we can INDIRECTLY know of them or at least gain good grounds for suspecting their existence... there are two fairly strong excuses for believing in universes in large numbers... mightn't it be absurdly complicated to think of this [Big] Bang as the only one ever to occur in that fashion?... The visible universe is not nearly dense enough to end at precisely those limits if General Relativity is even approximately right... The second excuse ... [is that] the present of vastly many universes very different in their characters might be our best explanation for why at least one universe has a life-permitting character." (Pg. 69-70)

He points out, "the existence of other universes would in no way reduce the luck that we had had if, say, our universe's early symmetries had just chanced to break life-permittingly, and ... their existence could none the less reduce our amazement by providing a field enough to give a fair chance that life-permitting conditions would be being observed somewhere..." (Pg. 141-142)

He criticizes a teleological theistic argument: "Sympathetic though I am towards theistic explanations, this seems to me a pointless muddying of the waters. What is the use of a Principle which can mean just whatever you wish it to mean? How is anyone to understand anyone else if Strong Anthropic Principle talk can be EITHER observational evidence selection effect talk OR ELSE teleological/theistic talk OR ELSE some mixture of the two and perhaps other things as well?" (Pg. 145) He also notes, "any fine tuning is just an illusion of us Earthlings. Intelligent living organisms might often be very unlike those on Earth, and much less fussy in their requirements. They might stand in no need of chemistry, for example, or of planetary surfaces to inhabit." (Pg. 186)

He summarizes, "I need to say why the God hypothesis strikes me as non-silly, and even as every bit as plausible as the many-universes hypothesis." (Pg. 161) He admits that "The Problem of Evil is certainly strong enough to make theism an uncomfortable position." (Pg. 187) But he concludes, "fine tuning can only very implausibly be dismissed as an illusion of Earthlings. We thus seem forced towards the hypothesis of many and varied universes, or the God hypothesis." (Pg. 189)

He adds, "My argument has been that the fine tuning is evidence, genuine evidence, of the following fact: that God is real, and/or there are many and varied universes." (Pg. 198) He reiterates in the book's final paragraph, "God is real and/or there exist many, very varied universes. Independently of all such evidence it is certainly hard to give a figure for the probability of that truth. Yet when we see the evidence, the conclusion to be reached can be plain enough." (Pg. 204)

This is a very thought-provoking discussion, that considers the “many universes”/multiverses argument in much greater detail than, say, a Richard Dawkins or Kenneth Miller does.