Missing the point on Fine-Tuning

The Fine-Tuning argument (henceforth the FTA) is the argument that the universe appears fine-tuned to create life, this strongly argues for the existence of a creator with life-friendly intentions.  I've written about the FTA before, in 2009, and I also endorsed a paper written by Ikeda & Jefferys¹ (henceforth I&J) which purports to refute the FTA.  I've now changed my mind, and no longer agree with I&J.

To briefly summarize I&J, they formulate the FTA in bayesian terms.  We already know that life exists, as part of our background knowledge.  The new piece of evidence put forth by the FTA is that the universe is such that life may arise naturalistically (ie it is "life-friendly").  I&J say the problem is that this evidence argues against supernaturalism, not in favor of it.  After all, in a naturalistic world, we must observe that the universe is life-friendly.  In a supernaturalistic world, we might observe otherwise, since supernatural intervention can create or sustain life even when natural laws are not life-friendly.

In formal terms:²

N = universe is naturalistic
L = life exists
F = universe is life-friendly

I&J show that
P(N|F&L) ≥ P(N|L)
Whereas the FTA requires that
 P(N|F&L) << P(N|L)

I think their theorem is basically incontrovertible,³ and I do not contest it. However, I feel it is missing the point.  Here I aim to explain why.

What does the Fine-Tuning argument argue?

A schematic illustration of the Fine-Tuning argument.  The two rows each represent a different meta-theory of the universe.  The colored bars represent the probabilities of different events within those meta-theories.

The FTA asks us to compare two meta-theories of the universe: naturalism and supernaturalism.  In a naturalistic universe, there's a very small probability that life can arise, because the universal constants need to be just right (or so the argument goes).  In a supernatural universe, well, who knows?

I&J make two important points about this argument.  First, they argue that the premise is irrelevant, and the conclusion is a fallacy.  Formally:

Premise: P(F|N) << 1
Fallacious conclusion: P(N|F) << 1

I checked to see if this is in fact the premise and conclusion used by FTA proponents.   The Discovery Institute basically makes the following argument:

Premise: P(F|N) < P(F|~N)
Conclusion: P(N|F) < P(N)

This is similar to the fallacious reasoning identified by I&J, only it's not fallacious.  It's correct.  But it requires a stronger premise.  Namely, we have to assume that the probability of life under naturalism is less than the probability of life under supernaturalism (as illustrated above).

I believe that I&J reject this stronger premise, and I think this is reasonable.  Who is to say that a deity would be particularly likely to arrange the universe such that it contains life?  There are an infinite number of possible deities which each prefer a different configuration of the universe.  If we only speak of deities that have an inclination towards universes with life, then they're likely to create life, but this is just some sort of selection bias on our part.

But even though I tentatively agree with I&J's first point, I will ignore it for the rest of the post, because I wish to evaluate how their second point stands on its own.

I&J's second point is that we need to include all evidence in our Bayesian.  We know two things: life exists, and life can arise.  The probability of naturalism should be conditioned on both these facts, not just one or the other.  Formally:

FTA argues that P(N|F) > P(N)
But the relevant comparison is between the quantitities P(N|F&L) and P(N|L)

With this modification, I&J find that if the universe is life-friendly, this is evidence against the supernatural.  This is easy to see in the above figure.  If we rule out a life-unfriendly universe (the red bar), this decreases the likelihood of supernaturalism.

On the other hand, if we compare the size of the green bars, it seems like the FTA works.  If the universe is life-friendly, that is evidence for naturalism.  But if the universe has life in it, it seems like that's even stronger evidence for the supernatural.  In formal terms, it appears that

P(N|F&L) ≥ P(N|L) << P(N)

And that's why I feel I&J have missed the point.

Life-friendliness vs Life

The "fine tuning" argument isn't "What do you think about God, when you learn that you are alive?" but "What do you think about God, when you learn that the universe is (apparently) fine-tuned or life-friendly?"
--Ikeda & Jefferys

As in the quote above, I&J believe that the only piece of evidence advanced by the FTA is that the universe is life-friendly.  The existence of life is not a piece of evidence, because we already knew life existed.

The thing is, the distinction between "life exists" and "life can arise naturalistically" is a novel idea by I&J.  It is definitely a useful distinction that improves our understanding of the problem.  But I don't think FTA proponents ever make this distinction.  FTA proponents are vague about it, and may not even know themselves whether they are arguing about life-friendliness or life-existence.

Therefore, when I&J say that FTA proponents are using life-friendliness as evidence, and not life-existence, this is totally groundless.

To understand the distinction between life-friendliness and the existence of life, it may help to consider how we might demonstrate life-friendliness.  It's actually very difficult to demonstrate without any sort of presumption of naturalism.  I&J indirectly mention the triple-alpha process, wherein the helium inside of stars fuse to carbon.  Since the triple-alpha process is necessary to naturalistically produce carbon life-forms, Fred Hoyle predicted in the 1950s that there was a particular resonance which greatly increased the probability of the triple-alpha process.  This prediction was later confirmed.

If FTA proponents are truly using life-friendliness as their evidence, they would point to Fred Hoyle's confirmed prediction.  In Biologos treatment, they do discuss the triple-alpha process, but do not mention Hoyle's confirmed prediction.  Instead they talk about how "statistically unusual" the resonance is.

Put in formal terms, I&J say that we should compare the quantities P(N|F&L) and P(N|L), because this is the correct comparison, and because this is the comparison described by FTA proponents themselves.  But I think that FTA proponents are actually comparing P(N|F&L) and P(N).  Furthermore, I think FTA proponents have chosen the correct comparison, whereas I&J have chosen the wrong one.

Trickiness with priors

But what is P(N|L)/P(~N|L)? Why, it is just the prior odds ratio that You assign to describe Your relative belief in N and ~N before You learn that F is true.
--Ikeda & Jefferys

According to I&J, our prior beliefs are based on our knowledge that life exists.  We think, therefore we are.  Therefore, if upon seeing that life exists, you think that supernaturalism is more likely than naturalism, then you have a "prior commitment" to supernaturalism.

"Prior commitment" sounds bad, like you've decided your conclusions before you've considered the evidence.  But generally speaking, there's nothing wrong with coming to conclusions without evidence, if you have an a priori argument.  Since FTA proponents are arguing about the quantity P(N|L), which I&J call a prior probability, we could say that FTA is partly an a priori argument.

Is it really true that the FTA is an a priori argument?  If the only evidence advanced is the existence of life, then the FTA is quite similar to the cosmological argument.  The cosmological argument only advances the evidence that there exists something rather than nothing.  Is the cosmological argument considered an a priori argument?  The internet consensus seems to be not.⁴

If the FTA is not an a priori argument, then I&J have made an error in using P(N|L) as our prior belief, rather than P(N).  If the FTA is an a priori argument, then I&J have basically ignored the a priori component of it, and no wonder that what remains is so unconvincing.

Of course, it seems like FTA proponents really are trying to advance some sort of evidence, and that's why they talk about universal constants and the triple-alpha process.  I propose that what's happening is that we're actually comparing three meta-theories:

By eliminating the naturalistic theories where fine-tuning is not necessary, it seems we greatly reduce the probability of life existing within naturalism.

Conclusion (TL;DR)

Ikeda and Jefferys refute the Fine-Tuning argument by making an interesting and useful distinction between universes with life, and universes where life can arise naturally.  According to them, it is only necessary to consider the evidence that life can arise naturally.  The problem is that this ignores the main thrust of the Fine-Tuning argument.

To refute the Fine-Tuning argument, we must discuss its many other problems, and not the particular problem put forth by Ikeda and Jefferys.

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1. Also see the same paper hosted on a different website with inferior design, but with the extra Appendix 2.

2. If you are unfamiliar with the formalism of conditional probabilities, you can read up on it.  In this post, I will try to minimize formalism, but it is impossible to eliminate it entirely.

3. The only assumption is that P(~F&L&N) = 0, which is true from the definition of F.

4. See here, here, and here, all search results for the cosmological argument.

Labels and self-advocacy

This was cross-posted on The Asexual Agenda.

I'm generally in favor of accepting identity labels even if they seem strange or confusing at first.  But there isn't any fundamental principle that identity labels should never be questioned.  The underlying principles are: 1) People using the identity label for themselves have thought about it much more, and have likely already considered whatever "concerns" I might think of in the first minute, 2) Repetitive questioning of people's identities causes more discomfort than light.

Both of these principles rely on the existence of people who actually use the identity label for themselves.  If someone creates a new identity label, and does not use it for themselves, the label is fair game for criticism as far as I'm concerned.  That's the problem with this graphic, created by someone on AVEN:

It's clear that the creator wanted to come up with as many romantic labels as possible.  In some cases they made up new labels by joining known prefixes with the "romantic" suffix.  Here are my comments on a few of them:¹

• "Transromantic" is problematic.  You can't really be attracted to trans* people as a general category, because all they have in common is their history of being assigned the wrong gender.  It makes about as much sense as saying you're oriented towards people who grew up in single-parent households.

• "Neutroisromantic" isn't problematic per se, but I'm unsure that people who are romantically attracted to neutrois people would really want to be known as neutroisromantic.  Maybe they'd prefer to come up with their own term?

• Based on the colors, the creator seems to have confused "polyromantic" for "polyamorous".²  This is the sort of mistake you'd make if you just heard the word "polyromantic", but were not familiar with anyone who identifies as such.

• "Lithromantic" stands in contrast to the other words, because it was clearly not made up.  It refers to people who don't need their romantic feelings to be reciprocated.  It's not really the sort of term you would make up independently, since "lithro" isn't a common prefix.

I'll admit that I find the concept of "lithromantic" a bit strange, but I won't say anything negative about it because there are in fact people who identify as lithromantic.  I'd rather let lithromantics speak for themselves!  In contrast, transromantics will not speak for themselves because there aren't really people who identify as transromantic.

The key is self-advocacy.  Identity labels are not sacred, but we trust in the self-advocacy of people who choose those labels for themselves.

Usually, identity labels only become problematic when they reach beyond self-advocacy.  For example, I don't like when people use "pansexual" because they believe that "bisexual" requires accepting a gender binary.  I don't like when people use "agnostic" because they believe that "atheist" means being absolutely sure.  Not that there is any problem in general with the terms "agnostic" or "pansexual".  But when these labels are used to say something about other people, that's fair game for criticism.

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1. I am not trying to slam the creator here.  It's okay for people to create imperfect things, and the graphic is just a harmless discussion-starter.

2. Polyromantic is analogous to polysexual, which means attracted to multiple genders (though not necessarily all genders).  It is not analogous to polyamory, which refers to having relationships with multiple people simultaneously.