There seems to be some ambiguity with the use of the word "chance" in this thread. Allow me to clarify please.

The principal use of the word, is to refer to something which is possible. "There is a chance that X will occur." This use lends itself to the concept of contingency, a contingent event being one which is dependent on something else, possible. The contingent event is one which is possible, it may or may not occur. Therefore there is a chance that it may occur. Notice that "chance", and "contingent", when used in this way, refer to something which is possible, in the future.

That is not the way that I used "chance" in the op. I used it in another way, which is defined as "the absence of design or discoverable cause". When we talk about existing things, and occurrences which have taken place in the past, and call them chance events, this is the way "chance" is used.

Modern proponents of Darwinian evolution posit random (chance) mutations as the cause of variation, and this is directly opposed to Lamarck's position of habituation. — Metaphysician Undercover

I believe that the art of husbandry demonstrates to us that physical variations are most likely not the effect of chance. — Metaphysician Undercover

StreetlightX appears to desire confusing the issue through equivocation, first using "chance" in my way, in one post, then using it in the other way in the following post. Failing to properly distinguish these two uses of "chance" only propagates the myth of chance, through the apparent contradiction that something with an "absence of design or discoverable cause", is also caused. This allows those who support "chance" to argue that there is no design or discoverable cause behind things such as some specific mutations, yet these things are still caused. Does this indicate that there is a belief within the scientific community that there are causes which are undiscoverable? What type of causes would these be, final causes?

'External chance' is what happens when an environment changes. — StreetlightX

Why would you call this "chance", something which has deterministic causes. If the weather forecaster forecasts no rain for tonight, then it rains, would you say that this was a chance event, even though there are identifiable causes for why the forecast was wrong. Why would you say that changes to an organism's environment are chance events?

Modern evolutionary theory today however recognizes that these changes aren't all entirely random; that in fact, there are mechanisms of mutability that in certain circumstances, force or otherwise increase the chances for variation. Another way to put this is that evolution has evolved mechanisms to increase evolvability; it's the ability of evolution to feedback upon itself that accounts for the relative 'rapiditiy' of evolution. — StreetlightX

If there are mechanisms of mutability at work here, which are assumed to act in a way to minimize randomness, why assume that these came about through some random process? It doesn't make sense to assume that a non-random process evolved from a random process.

According to the way that I laid out the principles of trial and error, even if the first trial is a random choice, the mechanism to judge, remember, and produce the next trial, must already be in place. And if this is the case, then the first trial is not actually random, it is chosen by that mechanism.

I confess I can't made heads nor tails of the OP — StreetlightX

When the two possibilities are heads and tails, the third option is to not flip the coin, or not read the results. Your so-called inability to make heads nor tails of the op is an expression of that third option, refusal.

The question is why the existing empirical evidence doesn't satisfy you. — jamalrob

I'll explain why the existing evidence doesn't satisfy me. Any so-called random occurrence only happens within very specific parameters. This is necessarily the case, or else any form of randomness would be absolute randomness A coin toss is constrained to two possibilities. A toss of a die is constrained to six. A draw in a lottery is constrained to the number of possible combinations.

If the parameters are defined, and the method of randomly choosing one of the numerous possibilities is verified as truly random, then we have evidence that the possibility which actually occurs is truly a random occurrence. But when the parameters of possibility are unknown, and the method by which one possibility out of the numerous possibilities is produced, is unknown, then where is the empirical evidence of randomness? Randomness is proven by knowing the parameters and the method. The unknowns here act as evidence against the likelihood of randomness.

But neo-Darwinism does not require "randomness" or "chance", but simply that there is no mechanism for systematically feeding back to the genome. It is essentially a mechanism of trial and error. — tom

Trial and error consists of a number of essential elements:
1. The choice of a trial
2. Associating the effects of the trial toward some intention, or judgement of the effects, concerning good and bad.
3. Remembering the association mention in #2
4. Applying what is remembered in #3 toward the choice of a future trial.

If your claim is that genetic mutations are typified as trial and error, then clearly there is a mechanism for systematically feeding back, as this is an essential aspect of trial and error. In trial and error, we learn from the mistakes, such that we do not repeat them. This is facilitated by memory. What is a gene other than a basic form of memory? And what is it remembering other than a past successful trial? So why do you not believe in #4? Why do you not believe that the gene itself, as #3, would influence the choice of a future trial (mutation). .

If this is the case, then the mutation is not random, the parameters of possibility for mutation, and the means for choosing one possibility out of the many, are directed by a process of trial and error.This is what we can call "progress". But this necessitates that the trials (random mutations) are not actually random. The parameters of possibility, and the process of selecting a possibility are evolving.

Lamarck was wrong about the basics of evolution. Darwin was right. Epigenetics is an interesting addition to modern evolutionary theory that demonstrates that Lamarck's approach was not entirely misdirected — Baden

I dislike how you make the unqualified assertion, "Lamarck was wrong", then you proceed to qualify this with "Lamarck's approach wasn't entirely misdirected". Why make such an assertion when you're only going to back it up with such indecisiveness?

It's not clear to me why you think that random mutations accreted over time through human selection are not enough to produce the changes we see in husbandry. — Baden

Let me get back to some examples then. I mentioned the horse. The horse didn't suddenly get much bigger than it was, with one sudden chance mutation which was selected for. The horse evolved in a way that it continuously got bigger over an extended period of time. If changes were random, and selected for, it would have gotten bigger, then all the other billions of random possibilities would pass randomly, as we would expect according to odds, before it randomly got bigger again. Instead it continuously got bigger and bigger. Either the possibilities for change were severely restricted, such that getting bigger kept coming up over and over again, or the method for choosing a possibility was not truly random, such that getting bigger kept being drawn in the lottery an unusually large amount of times.

There are many examples, the root of the beet got bigger, the kernel of the corn got bigger. Now we have dogs, and breeders can increase particular traits at an extremely rapid pace. These are not one time random changes, but continual increases over generations. In the case of pit bulls, a relatively small number of dog breeders have produced traits so strong over a small number of generations, that they have become undesirable to the human population in general.

It's like I said to Wayfarer, if your neighbour kept winning the lottery on a fairly consistent basis, wouldn't you think there was something other than random selection going on.

As has been pointed out already, this represents a serious misunderstanding. Suffice to say that the mechanisms of sexual selection are well understood and covered in modern evolutionary theory. — Baden

Huh, jamalrob said the opposite, that it represented a fair understanding of the mechanisms of sexual selection. Why the adversity?

The notion of chance within Darwinian evolutionary theory is as much a myth as the notion of gravity is in Einstein's general theory of relativity. And the attempt to deny its essential role is honestly not worthy of serious discussion (unless you want to completely ignore the science). What is worth debating for a variety of reasons is the extent chance plays in evolution. — Baden

I intentional avoided the topic of "the role" that chance plays, because "role" implies purpose, and purpose implies intentional design. This would draw us directly into the issues which Wayfarer brings up, without first obtaining a fundamental understanding of what chance and randomness actually are.

Suppose I am to flip a coin, there is a random chance, 50/50, heads or tails. This random occurrence only plays a role if I act, or make a decision to act, based on the outcome. The coin flip itself is just a coin flip, it doesn't play a role in anything, on its own. However, the case is that I choose to flip the coin, and I choose to do this for the purpose of making a random choice. Now the coin flip plays a role in something, it is a designed act, and the outcome of that act has an influence on my future behaviour, and therefore all that follows from this. Without purpose, direction, the random act cannot play a role.

If I wanted to choose one out of six possibilities, I'd roll a die. If I wanted to choose one out of a large number of possibilities, I'd choose a random number between one and whatever number of possibilities I wanted, through a draw, or random number generator. In each case, the random, chance, occurrence is designed for a specific purpose, to choose one specific number out of a specific number of possibilities. And so the act which produces the random number plays a role in some bigger intentional act.

That is why I wanted to avoid the question of the role that chance plays. Once we assume that an occurrence is chance, or random, it necessarily follows that the parameters under which the chance occurrence occurs, were designed, or else the chance occurrence could not be playing a role in something. If instead, we look first to understand the parameters of possibility, and the act by which the one possibility is "chosen", out of the many, then we can come to understand if any aspect of evolution is truly "chance", and therefore necessarily designed.

It has also been expressed that Darwin, although presented natural selection as one of the means of evolution, did not reject the idea of Lamarck - acquired characteristics — charleton

I agree, Darwin did not flatly reject Lamarck's ideas of habituation. But Darwin was producing a refined scientific theory, adhering to empirical facts, unlike the speculative theory of Lamarck. So the evidence for variation through habituation, just wasn't there.

Suppose that someone wanted to prove, through empirical evidence, something like chance, or the randomness of random genetic mutations, how would one proceed?

So, like I was saying, Aquinas rather "bastardized" Aristotelianism. That's not to say that what he did was remarkable, but he certainly had an agenda to fulfill, it would seem. — darthbarracuda

Why would you call this bastardizing, when I said that what he did was create consistency between Neo-Platonist and Aristotelian metaphysics? Isn't this how knowledge advances, we build on what those who have gone before us have produced. Anytime two different people are working to conceptualize the same thing, work has to be done to create coherency between the two.

Suppose that you and I both had the idea of putting a rocket on mars. You took a look at my plan, and put the most applicable parts together with your plan, leaving behind the parts where I was mistaken, to come up with a plan better than your original plan. Why would you call this bastardizing my plan?

Of course he had an agenda to fulfill, don't we all? Or do you think we all ought to be lost souls, going whichever way the wind blows? I've tried that, going whichever way the wind blows, and you cannot subsist, because it tears you apart.

However going back to the beginning, it's difficult to see how exactly A-T metaphysics is different from plain ol' Aristotelian metaphysics. — darthbarracuda

For what it's worth darth, here's my opinion, and some things which you should consider.

Neo-Platonist and Aristotelian metaphysics are very distinct platforms. Plato had exposed the problems with Pythagorean idealism and cosmology, so the Neo-Platonists took a separate path from Aristotle in resolving these issues. The Neo-Platonists developed a stronger idealism with independent Forms, Such as the One, which are active in the creation of the sensible world which we know. Aristotle developed a type of materialism with active, eternal circular motions, as unmoved movers.

Neo-Platonism was accepted into Christian theology, mostly through the influence of St. Augustine, as the independent, immaterial Forms, were consistent with God and the angels. Aristotelian metaphysics was not brought into Christianity in this early time, and remained in the hands of the Arabs. In later times, with increasing exposure to the Arab world, through the crusades etc., Christian theologians became familiar with Aristotelian philosophy.

I believe it is important to recognize that Aquinas approached Aristotelian metaphysics from a firm Neo-Platonist foundation. Therefore his work was to interpret Aristotle in a way so as to establish consistency with Neo-Platonist principles. This involved selective referencing, and generally shaping the material to conform. I think that if an inverse situation had occurred, if one were to approach Neo-Platonic metaphysics from a stringent Aristotelian platform, such a consistency could not have been established. .

Lamarck (and Darwin by the way) assumed that traits acquired by parents were transmitted to their young. Epigenetics aside, we know that isn't true. — tom

Epigenetics aside? You mean, the rule holds as long as we put aside the vast quantity of evidence which goes against the rule. OK, so "that isn't true", so long as we ignore the overwhelming evidence that it is true. That doesn't make sense to me, does it make sense to you?

For your information charleton, I have read a substantial amount of Darwin's work, as I have of Lamarck's. Notice in the op, that I indicate the designation of "chance", or "random mutation" comes from modern theorists, not Darwin himself. I believe Darwin was more careful just to identify objectively, the scientific reality of such variations, without needing to assign a cause of them.

I don't agree Mayor.
When it is believed that there is a cause or reason for a particular occurrence, the cause or reason being unknown, yet the believer claims "chance" for this occurrence, this claim is deceptive. It is deceptive because what is claimed, "chance" is inconsistent with what is believed, "cause, or reason". When an individual claims "X is the case" while believing X is not the case, this is deception. There is no place for such deception in science.

I think it's obviously felt to be chance as distinct from design. As Nagel comments in his essay, Evolutionary Naturalism and the Fear of Religion, 'Darwin enabled modern secular culture to heave a great collective sigh of relief by apparently providing a way to eliminate purpose, meaning and design as fundamental features of the world. — Wayfarer

The issue here is not "design" specifically, because design implies some external agent as the designer and cause. What I am addressing is the cause which is within oneself. Do creatures, through their own choice of actions, consequently behaviour, influence the physical traits of their future offspring, as Jean Lamarck assumes? I believe that choice in sexual reproduction is an extension of this principle. Choice in this activity is a valid example of how one's behaviour influences the genetic traits of the offspring.

Jamalrob seems adamant that genetic mutations are, in some sense, random. But if we take as an example, an animal such as the horse, why does an animal such as this continue over time, to change in the same direction? It continued to get bigger and bigger. This is what we find in domestication, once a beneficial direction is determined, an organism will be encouraged to continually evolve in this direction. This characteristic of evolution can be noticed in most plants and animals involved in husbandry. It appears like the creature can be directed in its evolutionary changes. This is not supportive of Darwinian random change, it is more supportive of Lamarckian habituation.

Sure, "modification by mindful selection" takes a while, as Nils Loc indicates. But how much time is necessary for random mutations to cause the changes we observe, as compared to the time over which these changes have actually occurred? It appears to me like domestication causes radical changes over very short periods of time. Look at the many variations of dogs for example.

As Wayfarer says, random genetic mutations "can account for the development of very complex organisms or organs", but the question is whether this is the correct account. The problem with "chance" is that it doesn't decisively rule out anything, so that something which appears to be against the odds could still be ruled as chance. If your neighbour is winning millions in the lottery every five or ten years, he might claim that he is just lucky, but wouldn't you think that something other than chance is going on?

The question of chance is not an issue of whether the likelihood of mutation is affected by its beneficence because this draws us into the question of beneficial for what, diluting the objectivity which we desire. Is it beneficial to an individual's survival, or is it beneficial to reproduction, and therefore beneficial to the survival of the trait, or is it beneficial for something completely different than these two?

The question has to do strictly with the cause of such mutations. Beneficial mutations occur, that is an undeniable fact. What is the cause of them? It is wrong to single out "beneficial to survival", and claim that such mutations appear to be random amongst the multitudes of other mutations, because plants and animals are engaged in multitudes of activities and a particular mutation may be beneficial to any one of these activities, while the activity itself is not necessarily beneficial to survival. Thus the proportion of mutations which are actually beneficial is much higher than those which are "beneficial to survival", because they are beneficial to activities which are not conducive of survival. So when determining the proportion of mutations which are beneficial, we must determine all possible forms of benevolence. This means we have to look at the question in a different way, removing the subjective goal posts of "survival" which we have installed. The question is, is a plant or animal's own behaviour capable of influencing genetic modifications so as to support that behaviour in future generations. That is the point of Lamarckian evolutionary theory. And if this is the case, then words such as "chance" and "random" should be removed from our understanding.

We know that many genetic changes have identifiable causes, so they are not completely random. As John says, to think that "interactions with the environment in general cannot influence the occurrence of mutations" is an outdated idea. So why propagate this myth that mutations are random? If it's the case, as Mayor of Simpleton says, that "chance" just stands in for "unknown", then this is outright deception. To replace "I don't know the cause of X" with "X is a chance occurrence", is to claim that X is known to be a chance occurrence, when the individual making this claim truly believes that the cause of X is unknown.