Both arguments have a premise in common. So if you agree with that premise - namely that we have free will - which argument we should buy is a function of the comparable plausibility of the other premises. So, which is more plausible: that free will requires indeterminism or that determinism is true? I'm not sure. But at the moment I don't think free will requires indeterminism because I'm unclear exactly what indeterminism would contribute apart from some inexplicability.

(July 4, 2013 at 7:15 pm)bennyboy Wrote:

(July 3, 2013 at 9:49 am)pocaracas Wrote: "High-level" lol.
Heisenberg's uncertainty principle states that we cannot know precisely both the speed and position of any given particle....
But... just because we can't measure it, it doesn't mean that the particle can't be at a given location and with a given velocity... does it?
Well, all particles must have some length, so a precise position is a strange concept, unless you go for the position of the center, where QM gives you the maximum of the wave function... which tends to be the same.

However, on a slightly less nanoscopic level, these uncertainties become a bit less pronounced and statistics takes over... the averaged wave function gets interpreted as a probability distribution and you get a very accurate (as far we've been able to measure it) probability for each state of the particle.
And, armed with those probabilities, you can determine the what's going to happen and how often.

But what do I know? I'm just a low-level physicist...

Great news!

Okay, given the starting position of the balls in a lottery machine, and their tumbling time in milliseconds before being dropped down their little chutes for display, tell me the winning numbers. Or tell me what the weather will be like on my next birthday.

You will say, "If I had accurate enough information, and enough computational power, I COULD tell you those things." But that's like saying, "If I could go faster than the speed of light, I could . . ."

The reality is you can't calculate the individual particles of even a simple system, and probably will never be able to. You can calculate ONLY on the statistical level, and in many cases not accurately. This is hardly a strong enough foundation on which to establish an absolute philosopy like that of determinism.

First semester of college: the set of natural numbers, N.
They are infinite, I can't count them.
But we all know that they are countable.

Just because something is so complex that I , pocaracas, a mere human, even if aided by a super-computer, can't determine it's outcome, that doesn't mean that the determinism of that outcome isn't there.

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(July 4, 2013 at 7:32 pm)bennyboy Wrote:

(July 4, 2013 at 6:58 pm)pocaracas Wrote: My brain works based on the laws of physics.
Everything that happens in my head is then deterministic... highly complex, I'll grant you that, but determined by the laws of physics... even if we may have missed some of them.
My brain sends electrical impulses which cause my body to move and type these things on this forum.

Do you have any reason or evidence that states that the brain works non-deterministically?

Show the rules by which physics manifests as subjective awareness-- and not just the appearance of it.

This whole thread is basically a process of begging the question-- "Well, we know that everything is dictated by the rules of physics, including the brain. Therefore, the mind is deterministic." I have a serious problem with this, for three reasons:
1) Nobody has created a physical description of mind, or interacted directly with one. Nobody has measured one, created one, or even provably destroyed one. Nor have you explained in a sensible way why the subjective perspective exists at all in a universe which could function perfectly well without it.

2) You are assuming that because the mind is supervenient on the brain, it cannot offer anything beyond the function of the brain. That's like saying "Casablanca is just a complex interaction of QM particles, and doesn't offer anything beyond the function of a movie projector"-- it doesn't actually explain how something like Casablanca exists, or describe its symbolic importance to the human minds watching it.

3) You ( and by this I mean you and the other physical monists ) keep asking people to furnish evidence that any competitor to the physical monist determinism you take as the default is wrong/incomplete. However, at no point have you actually established the truth of determinism, particularly with regard to mind. Instead, you point to brain function. However, this begs the question-- kind of the point of non-determinism is that mind on some level transcends the pure physical mechanism of the brain. As for evidence, I take as evidence the existence of the subjective perspective, aka sentience, itself. Why should a purely objective physical process manifest as subjective awareness? So far, Dennett has made the most famous attempt at this, but I find it pretty unconvincing.

Now, go back and tell me where I used the concept of "mind"... -.-'

But if you're so eager to use it, here: to me, mind is the high-order perception we have of brain functions.

Think of this "order" as programming classes.
You start with the basics: integers, floats, strings, functions. Build a class with them. Then build another and another, and another.... Then you start building classes that have these other classes in them. And then go up an order.
Keep going up and, at some point, you have no notion of the basics and everything seems to work as if by magic.

A human brain has billions of neurons arranged in a highly complex network. How does that network work? no one knows... although new models keep popping up.

No brain scan has detected an external energy floating by...
Missing parts of the brain represents missing parts of the person's psyche, the person's mind.
So, as far as I see it, the brain is the source of the mind and that should be the default position.

(July 4, 2013 at 7:46 pm)pocaracas Wrote: Now, go back and tell me where I used the concept of "mind"... -.-'

You didn't. You used the word "brain." You wouldn't use the word mind, because while it's central to our reality, it's not something that can be either seen or manipulated with any mechanical means.

Why is this important to this discussion? Because determinism is the argument that: 1) any physical system can only have one possible outcome; 2) the universe consists of nothing but physical systems.

Until you can adequately explain WHY brain function is experienced as sentience, then I consider that the elephant in the room.

Quote:But if you're so eager to use it, here: to me, mind is the high-order perception we have of brain functions.

Think of this "order" as programming classes.
You start with the basics: integers, floats, strings, functions. Build a class with them. Then build another and another, and another.... Then you start building classes that have these other classes in them. And then go up an order.
Keep going up and, at some point, you have no notion of the basics and everything seems to work as if by magic.

Okay. So lets say you came across Windows, and had no knowledge of the culture that made it. Would it be useful to say, "I don't know exactly what makes Windows work, but it's just a bunch of mechanical processes"? You might say yes. I'd say, there's something else going on, which is much more important than the specific mechanism upon which Windows supervenes. I wouldn't use the existence of Windows to prove determinism; if anything, I'd use it to demonstrate that behind apparently deterministic process, you may find mind.

Quote:No brain scan has detected an external energy floating by...
Missing parts of the brain represents missing parts of the person's psyche, the person's mind.
So, as far as I see it, the brain is the source of the mind and that should be the default position.

No brain scan has detected the existence of mind, either. You show me a magic Mind-o-meter 2000 that beeps when it detects "mind," and I'll show you a machine that measures brain function, and accepts the philosophical assumption that where function X occurs, mind has occured.

I don't want to derail the thread with mind/matter discussion exclusively, but I think it's important to determinism, as well. For most of us, I think determinism is really about whether we have free will, and the moral and social consequences if we arrive at a model in which we do not. It is my position that ideas have a kind of life of their own, supervient on SOME mechanism, but independent in nature of any particular mechanism.

(July 4, 2013 at 10:19 pm)bennyboy Wrote: Why is this important to this discussion? Because determinism is the argument that: 1) any physical system can only have one possible outcome; 2) the universe consists of nothing but physical systems.

No, the notion that any physical system can have only one outcome is pre-destination, not determinism. Determinism is the view that future physical states are determined by past physical states; nothing more. This is why substance dualism is a challenge to determinism because if substance dualism is correct, and the mind is beyond the physical, then future states are determined by past physical states plus whatever contribution the non-physical mind makes to the outcome.

(July 4, 2013 at 7:32 pm)bennyboy Wrote: This whole thread is basically a process of begging the question-- "Well, we know that everything is dictated by the rules of physics, including the brain. Therefore, the mind is deterministic." I have a serious problem with this, for three reasons:
1) Nobody has created a physical description of mind, or interacted directly with one. Nobody has measured one, created one, or even provably destroyed one. Nor have you explained in a sensible way why the subjective perspective exists at all in a universe which could function perfectly well without it.

2) You are assuming that because the mind is supervenient on the brain, it cannot offer anything beyond the function of the brain. That's like saying "Casablanca is just a complex interaction of QM particles, and doesn't offer anything beyond the function of a movie projector"-- it doesn't actually explain how something like Casablanca exists, or describe its symbolic importance to the human minds watching it.

3) You ( and by this I mean you and the other physical monists ) keep asking people to furnish evidence that any competitor to the physical monist determinism you take as the default is wrong/incomplete. However, at no point have you actually established the truth of determinism, particularly with regard to mind. Instead, you point to brain function. However, this begs the question-- kind of the point of non-determinism is that mind on some level transcends the pure physical mechanism of the brain. As for evidence, I take as evidence the existence of the subjective perspective, aka sentience, itself. Why should a purely objective physical process manifest as subjective awareness? So far, Dennett has made the most famous attempt at this, but I find it pretty unconvincing.

All valid points, until you get to the bolded part. Here you appear to be making an argument from ignorance, and that is not valid. Another person's inability to furnish a physicalist explanation for subjectivity counts as zero evidence in favor of other explanations.

(July 4, 2013 at 10:19 pm)bennyboy Wrote: Until you can adequately explain WHY brain function is experienced as sentience, then I consider that the elephant in the room.

Indeed.

(July 4, 2013 at 6:12 pm)Koolay Wrote: Right but whatever you are saying right now is to convince people to change their minds for determinism, so you are a thousand times more illogical than anyone that believes in free will by your own definition.

Only if he believes people changing their minds is a matter of choice - which he has in no way indicated is the case.

(July 4, 2013 at 6:12 pm)Koolay Wrote: Doesn't that make you way more illogical than me then? I believe in free will, so I have an actual reason for trying to convince people to accept the position. But you think people are like rocks, so you don't actually have a reason for interacting with anyone, you failed your own test of logic.

If you know I am a rock, what are you doing talking to that rock? Surely you are wasting your own time and my time.

You do realize that living in a deterministic universe doesn't automatically make people rocks, right?

Even if your utterly ridiculous conception of determinism was true, his position would still be logical. The reason for his trying convince others to accept his position is that due to the past events of his life, he is hardwired to do so. He is hard-wired to try to change your wiring through debate and discussion so that your position closely matches his.

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(July 4, 2013 at 7:18 pm)Koolay Wrote: My evidence is simple, by the sheer fact that people are trying to convince me that determinism is true is testament to the fact that they themselves accept that I have choices. They do the argument for me.

As said before, that is ridiculous. As demonstrated earlier, I can try to convince you without accepting that you have a choice in the matter.

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(July 4, 2013 at 7:24 pm)Inigo Wrote: Want an argument for the compatibility of free will and determinism? Here's one (it is very simple)

1. Determinism is true
2. We have free will.
3. Free will is compatible with determinism

Given that both 1 .and 2. are yet to be proven - no.

(July 4, 2013 at 6:12 pm)Koolay Wrote:

(July 4, 2013 at 9:51 am)Red Celt Wrote: Free will is a delusion. A very attractive delusion, but a delusion nonetheless. Of course, we don't like the idea that everything we do was pre-determined as an inevitability at the point of the Big Bang... but if you can't accept that conclusion, you'll have to find a source for your alleged free will.

We are but billiard balls rolling across a green baize - magnified by several levels of complexity. As a materialist, I'd like to see some evidence of the ghost that alters the paths of those balls.

Right but whatever you are saying right now is to convince people to change their minds for determinism, so you are a thousand times more illogical than anyone that believes in free will by your own definition.

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I am attempting to do no such thing. Live in whatever reality bubble that you wish to inhabit. I was just stating some facts - or, more accurately, my interpretation of the available evidence. I may well be wrong. If I am, that hasn't been shown by you... because you clearly don't understand what determinism is.

Falling rocks changing brain chemistry? WTF?

Think of all living entities as machines. Because that's basically what we are. Machines that have evolved, crafted and shaped due to the environments that they (and their ancestors) inhabited.

Now explain where free will comes from.

(July 5, 2013 at 1:53 am)apophenia Wrote:

(July 4, 2013 at 10:19 pm)bennyboy Wrote: Why is this important to this discussion? Because determinism is the argument that: 1) any physical system can only have one possible outcome; 2) the universe consists of nothing but physical systems.

No, the notion that any physical system can have only one outcome is pre-destination, not determinism. Determinism is the view that future physical states are determined by past physical states; nothing more. This is why substance dualism is a challenge to determinism because if substance dualism is correct, and the mind is beyond the physical, then future states are determined by past physical states plus whatever contribution the non-physical mind makes to the outcome.

I'm not familiar with this refinement of the word "determinism." To me (and in philosophical discussions I've seen with Dennett and others), it refers to the idea that what is could not have been other than it is. Dennett likes to talk about things being inevitable and "evitable."

Quote:

(July 4, 2013 at 7:32 pm)bennyboy Wrote: 3) You ( and by this I mean you and the other physical monists ) keep asking people to furnish evidence that any competitor to the physical monist determinism you take as the default is wrong/incomplete. However, at no point have you actually established the truth of determinism, particularly with regard to mind. Instead, you point to brain function. However, this begs the question-- kind of the point of non-determinism is that mind on some level transcends the pure physical mechanism of the brain. As for evidence, I take as evidence the existence of the subjective perspective, aka sentience, itself. Why should a purely objective physical process manifest as subjective awareness? So far, Dennett has made the most famous attempt at this, but I find it pretty unconvincing.

All valid points, until you get to the bolded part. Here you appear to be making an argument from ignorance, and that is not valid. Another person's inability to furnish a physicalist explanation for subjectivity counts as zero evidence in favor of other explanations.

I don't accept the idea that "substance dualism" (I'll use that word from now, though I just call it dualism) is an explanation of mind. It is a description of observation: I have a mind, and this mind perceives things. Any candidate for Master of the Universe (Theory) has to explain to me in meaningful terms why there is mind, and why there are objects for the mind to perceive.

I'm not bothered if you call this an argument from ignorance, as I'm not positing a theory about what mind is. I'm just saying that my experience of the thing called mind doesn't accord well with the theory which people are demanding be considered the default position. BOP goes on those with the theory, not on those who are describing their direct experience.

The mind is effectively the software running on the hardware of the brain. They are both physical.

A question to dualists: how does a ghost drive a car?

(July 4, 2013 at 10:19 pm)bennyboy Wrote:

(July 4, 2013 at 7:46 pm)pocaracas Wrote: Now, go back and tell me where I used the concept of "mind"... -.-'

You didn't. You used the word "brain." You wouldn't use the word mind, because while it's central to our reality, it's not something that can be either seen or manipulated with any mechanical means.

Why is this important to this discussion? Because determinism is the argument that: 1) any physical system can only have one possible outcome; 2) the universe consists of nothing but physical systems.

Until you can adequately explain WHY brain function is experienced as sentience, then I consider that the elephant in the room.

Why do ask a why question here?

Had you asked a how question, how brain function is experienced as sentience, I'd reply with something along the lines of highly complex neural network, bla bla bla... we can't determine that with present tools bla bla bla...
But you ask "why"...
And a why in here, presupposes that some entity had some reason to do it like that... you can see where such a question leads, right?

(July 4, 2013 at 10:19 pm)bennyboy Wrote:

Quote:But if you're so eager to use it, here: to me, mind is the high-order perception we have of brain functions.

Think of this "order" as programming classes.
You start with the basics: integers, floats, strings, functions. Build a class with them. Then build another and another, and another.... Then you start building classes that have these other classes in them. And then go up an order.
Keep going up and, at some point, you have no notion of the basics and everything seems to work as if by magic.

Okay. So lets say you came across Windows, and had no knowledge of the culture that made it. Would it be useful to say, "I don't know exactly what makes Windows work, but it's just a bunch of mechanical processes"? You might say yes. I'd say, there's something else going on, which is much more important than the specific mechanism upon which Windows supervenes. I wouldn't use the existence of Windows to prove determinism; if anything, I'd use it to demonstrate that behind apparently deterministic process, you may find mind.

And despite your attempts to explain it as some independent thing, windows would still be just a series of instructions embedded on the computer running it. A physical deterministic thing.

Going back to sentience, think of it as a process running on windows... or a service, even.

(July 4, 2013 at 10:19 pm)bennyboy Wrote:

Quote:No brain scan has detected an external energy floating by...
Missing parts of the brain represents missing parts of the person's psyche, the person's mind.
So, as far as I see it, the brain is the source of the mind and that should be the default position.

No brain scan has detected the existence of mind, either. You show me a magic Mind-o-meter 2000 that beeps when it detects "mind," and I'll show you a machine that measures brain function, and accepts the philosophical assumption that where function X occurs, mind has occured.

fMRI.
Shows a clear relation between brain activity and function/action/thought....
But you're right, as I said, "No brain scan has detected an external energy floating by...", which is what I'm calling the mind in your case of it being apart from the brain itself...

(July 4, 2013 at 10:19 pm)bennyboy Wrote: I don't want to derail the thread with mind/matter discussion exclusively, but I think it's important to determinism, as well. For most of us, I think determinism is really about whether we have free will, and the moral and social consequences if we arrive at a model in which we do not. It is my position that ideas have a kind of life of their own, supervient on SOME mechanism, but independent in nature of any particular mechanism.

That's why, if you lose a piece of the brain, you lose a piece of your mind, right?...

(July 5, 2013 at 3:42 am)bennyboy Wrote: I don't accept the idea that "substance dualism" (I'll use that word from now, though I just call it dualism) is an explanation of mind.

In a discussion such as this one, as most people are only acquainted with physical monism and substance dualism. However, there is another view which is often discussed in the context of cognitive science and that is 'property dualism.' So, to be clear, it's probably a good idea to explicitly specify which type of dualism you mean, if you are referencing a non-monist ontology. (And I've just discovered that there is another dualistic ontology called .)

Patricia Churchland Wrote:The two primary foci for the dualist's conviction are the logical-meaningful dimension of cognition and the qualities of consciousness. The importance of these matters has struck dualist philosophers in different ways, with the consequence that some have gravitated to one focus and some to the other. One group has taken the nature of felt experience as the difficulty of paramount importance and hence has tended to side with materialists on the other question. That is, they expect that eventually the logical-meaningful dimension will ultimately have a causal neurobiological explanation. For these philosophers reasoning is not the stumbling block, partly because the idea that the logical-meaningful dimension of cognition is fundamentally noncausal is found objectionable. The second group has just the converse set of intuitions. Like reductionists, they think that ultimately consciousness and the qualities of felt experience will be explained in neurobiological terms. But for them, the difficulty of paramount importance lies in the logical-meaningful dimension of cognition. Here, they argue, are insurmountable problems for a reductionist strategy. The reductionist has been useful to both camps by providing reductionist arguments for each to use against the other. These dualist intuitions can be respectably sustained despite the hopeless problems of substance dualism in finding a coherent fit for the mind-substance in modern physics and biology. The general strategy in support of these intuitions has been to abandon the albatross idea of a distinct substance but to retain the idea of irreducibility. Thus, philosophers concerned with subjective experience have argued that subjective experience is an irreducible property, and philosophers concerned with the logical-meaningful dimension have argued for the irreducibility of cognitive theory. It is among these two, albeit inharmonious, groups that the most sophisticated antireductionist arguments are to be found, and characteristically they are not to be removed by a few casual rejoinders. …

… The nature of subjective experience has seemed to many people so striking and so extraordinary that it has been invoked repeatedly as the standing refutation of reductionism. The argument from subjective experience has been most powerful, not in the hands of the substance dualists, who have to contend with complications of their ghostly substance, but in the hands of the property dualists. Although there are nontrivial differences among the hypotheses advanced by assorted property dualists, the crux of the shared conviction is that even if the mind is the brain, the qualities of subjective experience are nevertheless emergent with respect to the brain and its properties. Subjective experience, goes the argument, has a character and a quality uniquely and irreducibly mental. Since the notion of a property's being emergent makes an appearance in this argument, an explication of "emergence " is in order. In general, whether a property is emergent is a function of the reductive relation that holds — or rather, fails to hold — between two theories or conceptual frameworks. More specifically, a property P specified by its embedding theory T1 is emergent with respect to the properties of an ostensibly reducing theory T2 just in case:

1. P has real instances,
2. P is co-occurrent with some property or complex feature recognized in T2 but nevertheless,
3. P cannot be reduced to any property postulated by or definable within T2 (Paul M. Churchland 1985)

As noted in the account of intertheoretic reduction outlined in chapter 7, the reducibility of one property to another depends on whether the theory that characterizes the property at issue reduces to the theory that characterizes the other. To put the matter informally, if a property of one theory has causal powers that are not equaled or comprehended by any property in the second, more basic theory, then the property is considered to be emergent with respect to the second theory. Accordingly, to claim that the qualitative features displayed in one's subjective experience are emergent with respect to the physical brain is to insist that the commonsense conceptual framework for apprehending and describing such psychological properties is not reducible to any future neuroscience.

Whether a property is emergent is therefore not a simple observational feature of the property, and so one cannot tell simply by inspecting a property whether or not it is emergent with respect to some other property, despite the conviction displayed by the occasional theorist lost in introspective reverie. (E. Nagel (1961) also points this out.) Nor of course do commonsense intuitions that two properties are substantially or even stunningly different entail anything about whether a future intertheoretic reduction might actually identify the two. Light may seem completely different from electromagnetic radiation, yet light turns out to be electromagnetic radiation. Having a high temperature seems supremely different from having a high mean molecular kinetic energy, yet it turns out that high temperture in a gas is high mean kinetic energy of the constituent molecules. Notice also that one does not provide independent evidence for the irreducibility of one property to another merely by claiming that the first is emergent relative to the second. That would be like saying of a property that it is irreducible because it is irreducible.

"Emergent property" is also used in the neuroscientific literature with a quite different sense roughly equivalent to "network property." Consider a set of cells in the retina that are wired so as to collectively constitute a movement detector, even though none of the individual cells is itself a movement detector. The functional property of being a movement detector may understandably be described as "emergent" relative to the individual neurons in the circuit. However, the functional property is certainly and obviously reducible to the neurophysiological properties of the network. Indeed, once we understand the network, we have the reductive story in hand. Although this is a useful sense of "emergence" (which Dennett calls "innocent emergence"), it is clearly not the sense intended by property dualists in their arguments against reductionism. Thus, when Sperry (1980) argues that mental states are emergent, he specifies that he means they are irreducible, not merely that they are network properties.

The claim that subjective experience is not reducible to brain states is to be understood within the wider framework of intertheoretic reduction, where it unpacks as the claim that psychology will not reduce to neuroscience; more specifically, that it will not reduce to neuroscience in such a way that subjective experiences can be identified with states of the brain. States of the brain are causally connected to subjective experience and give rise to the stream of events in awareness, the argument will agree, but the experience itself, with its unique qualities, cannot be identified with some process or aspect of neuronal activity. In contrast to the substance dualists, the property dualists do not believe there is a nonphysical substance in which experiences inhere. Rather, they claim that subjective experiences are produced by the brain and can in their turn affect the brain, but they are not themselves identifiable with any physical properties of the brain. On this view, we cannot say, for example, that feeling sad is a neuronal configuration in such and such a neuronal ensemble.

An analogy here may help. It has often been claimed that the blueness of (liquid) water is a property that is emergent relative to the microphysics of H2O molecules, on the grounds that no amount of microphysical information could allow us to predict or to deduce that liquid aggregates of such molecules would have the peculiar qualitative character we call "blue." Blueness may systematically co-occur with aggregates of H2O molecules, it is conceded, but it is a self-contained and irreducible property that appears in addition to the microphysical features of aggregated H2O. It is, in a word, emergent. Given the account of intertheoretic reduction outlined earlier, the fallacy of this reasoning is displayed with relative ease. For one thing, reduction does not require that reduced properties, as conceived within their older conceptual framework, be deducible or predictable from within the new reducing theory. Old frameworks are culturally idiosyncratic and highly various. It cannot be the obligation of new theories to predict how ignorant cultural epochs may happen to conceive of the complex phenomena in their explanatory domain. What they are obliged to do, if they are to achieve the reduction of earlier concepts, is nothing more and nothing less than to entail the existence of properties that systematically mimic the alleged causal powers of the properties to be reduced.

In the example at issue, the microphysics of H2O molecules does indeed entail that liquid aggregates of them will preferentially scatter incident electromagnetic radiation at a wavelength of about 0.46 μm. It is this complex property that proves to have all of the causal powers of blueness (at least as it is manifested in liquid water). This microphysical property affects human observers in all the same ways as does blueness. It affects nonhuman instruments in all the same ways as does blueness (for example, it projects light through a prism into the same spectral position as does blueness). And so forth. Because of these systematic parallels, it is reasonable to identify the blueness of an object with its disposition to scatter (or reflect, or emit) electromagnetic waves preferentially at about 0.46 μm. That is the property that humans have been visually discriminating for millennia, though without appreciating its fine-grained nature. The blueness of water, therefore, is not an emergent property. On the contrary, it reduces rather smoothly, and as a coherent part, of a systematic account in which the other colors are also reduced.

— Patricia Churchland, Neurophilosophy, pp. 322-26

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(July 5, 2013 at 3:42 am)bennyboy Wrote:

(July 5, 2013 at 1:53 am)apophenia Wrote: No, the notion that any physical system can have only one outcome is pre-destination, not determinism. Determinism is the view that future physical states are determined by past physical states; nothing more.

I'm not familiar with this refinement of the word "determinism." To me (and in philosophical discussions I've seen with Dennett and others), it refers to the idea that what is could not have been other than it is. Dennett likes to talk about things being inevitable and "evitable."

You may be being misled by the context of Dennett's remarks. Dennett is a compatibilist, which means that he believes that free will and determinism are compatible, if understood properly. Depending on when and where you read or heard Dennett, from his early work in Elbow Room to his later work, you may have been misled by his attempting to carve out a philosophical meaning of free will and choice that isn't at odds with determinism; this can result in some very fancy footwork. (Libertarian free-will theorists, not to be confused with the political philosophy, as well as hard determinists, both, see determinism as incompatible with free will, and resolve the dilemma by either denying determinism [libertarian theorists], or by denying free will [hard determinists]; compatibilists like Dennet try to split the baby, and thus may be using unorthodox or unfamiliar usage at different points in their rhetoric.) Anyway, It's been over a decade since I read Elbow Room in which the questions you are highlighting, evitability and could-have-done-otherwise, were pre-eminent. (His paper he co-authored with Taylor, I believe, talks about could-have-done-otherwise, but if I remember right, that was embedded in a framework of discussing counterfactuals in terms of possible worlds ala David Lewis. I read the majority of Freedom Evolves last year, but I don't recall specifically how prominent or not such analysis was in it.)

(ETA: An additional point to note is that Dennett is a physicalist (substance monist), and according to his understanding, the relevant features of the brain are all sufficiently macroscopic as to be described by classical mechanics and so forth — there is no indeterminacy, quantum or otherwise, to intervene and prevent state A from proceeding majestically to a classically predictable state B. That is why there is all the rather dense and convoluted talk in his texts on free will — he's attempting to preserve "the sense" of free will against a backdrop of assumptions [his] that most would conclude do not admit the possibility of free will.)