I was finishing up Malley's How the Bible Works last night and came across this interesting idea, one that is congruent with some thoughts I had a few years back but never really followed up on:
In Rappaport's model, the most fundamental premises of a society are its "ultimate sacred postulates" (USPs). USPs are distinguished from the other understandings present in a society in that USPs are nonempirical, beyond the reach of logical refutation, and regarded as unquestionable. Examples of USPs given by Rappaport are the Shema of Judaism and the Shahada of Islam. Such postulates have an important social function in that they define a community and thus serve as a kind of core around which the community can transform and adapt to circumstances while preserving its essential identity. It is important for this function that they be neither empirically nor logically falsifiable, because this shelters them from every having to change. Their nonempirical, often nearly tautologous nature makes them ideal foundations for community identity. (pp. 137-138)
This passage brings together a number of strands of scholarship without referring to any of them. For instance, it is resonant with my own interests in cultural robustness and evolvability. Note in particular how an instance of robustness, the unchanging nature of USPs, is said here to form a core around which a community can adapt. In other words, the presence of USPs allow a degree of evolvability by virtue of the fact that they can remain constant markers of group identity. Presumably, if group identity were not so robust, then the social boundaries of that community might have to be renegotiated with every adaptive change, thus risking group cohesion at every twist and turn of a community's evolutionary trajectory. The proximate mechanisms by which this robust trait is brought about is by placing USPs outside the realm of refutation, a very clever trick when you stop to think about it.
And, of course, this passage evokes, though likely unintentionally, Lin Ostrom's work. Clear social boundaries are part of the very first design principle. This naturally leads me to wonder if USPs might also accompany other design principles as well. My work on religion and natural resource management doesn't currently touch on this question, but it wouldn't take much effort to launch a study of USPs and design principles from this project. That isn't to say it wouldn't take a lot more work. We'd basically have to code each instance we've found of religion playing a role in a design principle for whether a USP is evoked or not. This might require more research into the specific beliefs involved than what we currently have in the database. However, it might not if we could get by ignoring the requirement that USPs be "regarded as unquestionable" and instead focus exclusively on whether they are "beyond the reach of logical refutation." For instance, I would be inclined to code the belief that ancestors are watching over a sacred grove as something beyond the reach of logical refutation. This point could be argued, but it wouldn't be a bad first approximation, and one we could use our existing coding of case studies to address.
Needless to say, Rappaport has moved to the top of my reading list...
I was going to start a new blog entry for this last quotation from Malley, but it seems closely related to these ideas so I'll just continue here. Malley makes the point that an important aspect of Evangelical Biblicism is the fact that the canonical texts are closed and well defined, making them clearly demarcated from other kinds of texts. He then goes on to say:
This conventional boundary affords a different kind of flexibility. By demarcating the boundary of scriptures very clearly, the content of the texts can be left unspecified. So long as evangelicals can know what counts as a biblical text, they do not need to have a very elaborate knowledge of what is in those texts. Their practice turns on establishing links between their ideas and some biblical text or other, and this can be done in ad hoc ways so long as one has some way of knowing what counts as a biblical text. The closure of the canon affords openness in interpretation. (pp. 150-151)
So once again we see an example in which robustness, in this case the rigidness of canonical boundaries, can lead to greater evolvability in the form of openness of interpretation. Good stuff!
This is a place for the members of the Wilson lab to support and challenge one another as they develop their projects.
Monday, May 28, 2012
Wednesday, May 23, 2012
Caught Between Scylla and Charybdis
It's been many years since I've seen the names Scylla and Charybdis. In fact, the last time I read those names was probably in middle school when I had something of an obsession for Greek mythology. With so many years elapsed, I had to refer to Wikipedia just to be sure I remembered them correctly and, though the details had largely vanished from my mind, I did still retain the basic idea. Scylla and Charybdis were two sea monsters situated on opposite sides of a narrow straight. Sailors making a wide berth to avoid Scylla, a six headed beast, ran the risk of coming too close to Charybdis, a formerly beautiful daughter of Poseidon who became a hideous bladder that sucked in and spit out water in the ocean to form whirlpools. Being caught between Scylla and Charybdis, then, is to be caught between a rock and a hard place, but with ghoulish monsters to make things more interesting.
So what brought these images back to my mind? They were used as a metaphor in Brian Malley's How the Bible Works to describe the tension Evangelicals face when transmitting their interpretive tradition:
The interpretive tradition is perennially caught between the Scylla of interpretive freedom and the Charybdis of irrelevance: to much hermeneutic freedom and the tradition disintegrates, loosing its epistemological appeal; too little interpretive freedom and the Bible becomes merely an irrelevant historical artifact, rather than the ever living word of God. (p. 124)
This is relevant not only to our collective work on tight vs. loose congregations but also to my own work on cultural robustness and evolvability. On the latter point, I find Malley's observations particularly illuminating and worthy of further research at some point down the road. According to him, the interpretive tradition received by lay people is relatively devoid of interpretive freedom. People aren't really reading the Bible to search for new meaning. Rather, they read the Bible in the search for relevance. They do become skilled in finding Biblical passages that confirm beliefs they hold, but in terms of their personal reading of the Bible, they mostly seek to find ways in which what they are reading can speak to their lives at the moment. When they find this kind of relevance, they perceive it to be God speaking to them through the intervening text. Note that this is a very different relationship with a sacred text than what is common in, say, Jewish tradition in which each generation is encouraged to wrestle with the Torah and Talmud in order to create new meaning that speaks to an evolving world.
So where, then, is the source for new interpretations in Evangelical traditions? How do they avoid the Charybdis of irrelevance? Malley locates at least a partial answer to this question in Evangelical seminaries. Ministers often undergo extensive training at institutions of higher education in which a true hermeneutic tradition is taught. New generations of pastors, then, have the opportunity to read the sacred text anew and engage in a Biblical scholarship that can open up new possibilities. Obviously, this is a relatively conservative process, constrained as it is by notions of what the previous generation of scholars, who are the current professors, deem acceptable deviance from the norms. Nevertheless, it is a fertile ground for at least some innovation and this, then, after undergoing its own kinds of selection processes, can leak its way into the more general population of believers, who will generally accept it without much critical thought. This dynamic strikes me as an excellent example of robustness and evolvability at work.
Wednesday, May 9, 2012
Mind = blown
I don't remember what specifically prompted me to order Brian Malley's How the Bible Works: An Anthropological Study of Evangelical Biblicism, but it arrived late last week and I've spent most of today devouring it. However the book captured my attention, it has so far been well worth the read and I have no doubt but that I'll be quoting it in our Bible as Cultural Genotype manuscript.
Of all the insights it's given me though, the one that stands out most strongly in my mind after a solid day of reading came in the introduction. I'm still trying to wrap my mind around it and its implications so for now I'll simply quote a thought provoking paragraph (p. 8):
The presumption of textual meaning, it seems to me, is a specific case of the general principle proposed by Dan Sperber and Deirdre Wilson (1995), that although humans generally transmit only partial and ambiguous representations of the messages they intend to communicate, listeners' presumption of an intended message's relevance enables them to select, from among the possible interpretations, the one intended by the speaker. On Sperber and Wilson's view, all communicative signals are partial and ambiguous representations of their intended messages. The recipients of signals are therefore confronted with the task of sorting out which of the possible interpretations is intended by the speaker. They are aided in this task by the speaker's implicit promise that the signal is as appropriate as possible for the intended message (Grice 1989). Sperber and Wilson give a cognitive explication of this promise: the speaker, in attracting the listener's attention and offering an utterance, implicitly guarantees that the informational value of the intended message is greater than the energetic cost of cognitively processing it. The listener recognizes this implicit guarantee, and selects the first interpretation that meets this standard of relevance. It may be that further interpretations could be explored with more cognitive effort, but once the promise of relevance is satisfied, interpretation stops. (Of course, the guarantee of relevance may not be given in good faith, or a speaker may misjudge the conditions of relevance for the listener, or a number of other things might go wrong but in general, the principle of relevance guides the listener to the speaker's intended meaning.) In ordinary conversations, then, interpretation is both initiated and guided by the expectation of relevant meaning.
In other words, "In a sense, the meaning arises only because it is presumed." (p. 8)
Food for thought, presuming of course that all this really means something.
Of all the insights it's given me though, the one that stands out most strongly in my mind after a solid day of reading came in the introduction. I'm still trying to wrap my mind around it and its implications so for now I'll simply quote a thought provoking paragraph (p. 8):
The presumption of textual meaning, it seems to me, is a specific case of the general principle proposed by Dan Sperber and Deirdre Wilson (1995), that although humans generally transmit only partial and ambiguous representations of the messages they intend to communicate, listeners' presumption of an intended message's relevance enables them to select, from among the possible interpretations, the one intended by the speaker. On Sperber and Wilson's view, all communicative signals are partial and ambiguous representations of their intended messages. The recipients of signals are therefore confronted with the task of sorting out which of the possible interpretations is intended by the speaker. They are aided in this task by the speaker's implicit promise that the signal is as appropriate as possible for the intended message (Grice 1989). Sperber and Wilson give a cognitive explication of this promise: the speaker, in attracting the listener's attention and offering an utterance, implicitly guarantees that the informational value of the intended message is greater than the energetic cost of cognitively processing it. The listener recognizes this implicit guarantee, and selects the first interpretation that meets this standard of relevance. It may be that further interpretations could be explored with more cognitive effort, but once the promise of relevance is satisfied, interpretation stops. (Of course, the guarantee of relevance may not be given in good faith, or a speaker may misjudge the conditions of relevance for the listener, or a number of other things might go wrong but in general, the principle of relevance guides the listener to the speaker's intended meaning.) In ordinary conversations, then, interpretation is both initiated and guided by the expectation of relevant meaning.
In other words, "In a sense, the meaning arises only because it is presumed." (p. 8)
Food for thought, presuming of course that all this really means something.
Monday, April 23, 2012
Two can play this game... :)
So here's a little radar diagram that I've done up to represent some of the things we discussed this afternoon. Specifically, it relates to the idea I had about mapping congregations in terms of their expressed levels of diversity on the horizontal axis and tolerance of diversity on the y-axis. If we further break diversity and corresponding tolerance down into beliefs, behaviours and demographics categories, we could arrange measures for specific faith communities as such:
If we could swap perceived for actual the above
schematic, then I think we’d have an interesting handle on what it means to be a
tighter faith community (i.e. a relatively
small surface area - Church B in this example). The problem with
this of course is that doing so would require a list of all the beliefs
individuals are supposed to subscribe to and getting a sense of existing drift for each community.
Not intractable, but certaintly not feasible for the moment. So we may be stuck with perceived. Actually, now that I think about it, having all three would be ideal - actual, perceived, tolerance. As it stands, “behavioural diversity”
is a little up in the air… do we mean life behaviours or worship/religious
behaviours?
Thoughts? Specifically, is surface area a decent measure of tightness? For example, what if group C is really high on diversity, but low on corresponding tolerance measures, and group D is low on diversity measures but really high on corresponding tolerance measures. Both would have the same area but be manifestly different groups. Clearly some distinguishing power is lost. Are both congregations effectively equally Tight but for different reasons? I don't think so, as one would be open to increasing diversity while the other is not. Does this mean the polygon created by the Tolerance axes is the Tightness measure and the other half really constitutes a Disparity measure between "ideal" and "actual" or "perceived"?
Sunday, April 22, 2012
Rules as Genotype: Random Reflections
As much as I enjoyed the workshop last week on the topic of "rules as genotype," I've been increasingly disappointed that nothing was really accomplished by the participants there. We had some amazing conversations, but we could never really get beyond various restatements of the metaphor. In the end, I believe the only conclusions were either that the metaphor was still viable or that it had run its course. No one, however, clearly articulated why they fell into one camp or the other and about the most useful comment was also the most obvious. Namely, when you argue from metaphor, trying to map concepts from one domain to another, you're bound to be wrong in the details.
Aside from having too many different disciplines at the table to make much progress in two days, I think the workshop went off course primarily because no one wanted to get his or her hands dirty hammering out the messy details of vocabulary. For instance, I don't recall anyone asking what a genotype was or what rules were or what aspects of a genotype rules were supposed to emulate. Yet these are fundamental problems that have to be overcome if there's to be any hope of progress on this idea.
Thankfully, there a number of thinkers who are taking the idea of universal Darwinism seriously and who have done at least some of the basic groundwork. I need to become far more familiar with this camp, but I believe Hodgson and Knudsen may have already answered this question in Darwin's Conjecture. I don't want to try to summarize their entire argument here, or at least not now. However, key to their argument is something they call a generative replicator. For them, replicators require four conditions:
Aside from having too many different disciplines at the table to make much progress in two days, I think the workshop went off course primarily because no one wanted to get his or her hands dirty hammering out the messy details of vocabulary. For instance, I don't recall anyone asking what a genotype was or what rules were or what aspects of a genotype rules were supposed to emulate. Yet these are fundamental problems that have to be overcome if there's to be any hope of progress on this idea.
Thankfully, there a number of thinkers who are taking the idea of universal Darwinism seriously and who have done at least some of the basic groundwork. I need to become far more familiar with this camp, but I believe Hodgson and Knudsen may have already answered this question in Darwin's Conjecture. I don't want to try to summarize their entire argument here, or at least not now. However, key to their argument is something they call a generative replicator. For them, replicators require four conditions:
- Causal implication: The source must be causally involved in the production of the copy, at least in the sense that, without the source, the particular copy would not be created.
- Similarity: the replicated entity must be or contain a replicator. The conditional generative mechanisms in the copy must be similar to those in the source. Errors or mutations in these mechanisms must also be copied with some degree of fidelity.
- Information transfer: During its creation, the copy must obtain the conditional generative mechanisms that make the copy similar to its source from that same source.
- Conditional generative mechanisms: Generative replicators are material structures that embody construction mechanisms (or programs) that can be energized by input signals that contain information about a particular environment. These mechanisms produce further instructions from a generative replicator to their related interactor that guide its development. (pp. 122-123)
So, are rules a kind of generative replicator? Before answering that, it's worth asking of genotypes are generative replicators. According to Hodgson and Knudsen the answer is yes. DNA cannot be replicated without the template, fulfilling the causal implication. the replicated entity, the nascent strand of DNA, most certainly fulfills the similarity and information transfer requirements. Moreover, the resulting daughter strands of DNA are capable of responding, through a variety of epigenetic mechanisms, to environmental inputs in order to guide development.
If we can accept Hodgson and Knudsen's definitions, then it seems the question we should have been asking at the workshop was, really, are rules generative replicators? Scanning the bibliography of Darwin's Conjecture, it looks as though Hodgson at least has already written a lot in this area that I should become more familiar with. Unfortunately, the closest they come to discussing rules in the institutional sense is their exploration of judicial law as a major transition (Section 8.5 and assorted other places within the book). For a variety of reasons I was unhappy with this particular discussion. Perhaps the most glaring disagreement I had with them was their insistence that judicial law requires writing. This simply flies in the face of historical fact, perhaps best exemplified in Icelandic law. None of that, however, is particularly relevant to the concerns here.
The authors argue that judicial law does constitute a generative replicator. The causal implication requirement is a bit vague, but it seems to be met at some level either when laws are copied to new states (one form of replication) or when new laws are written which tend to rely on existing legislation. It seems the argument here would be stronger if they included laws being passed from one generation to another, but I don't believe they consider this process in their formulation. At any rate, these same processes, along with judicial review, which tends to clarify and refine laws, ensure that the similarity condition is met. Undoubtedly, laws contain information so the copying of laws involves information transfer. Conditional generation occurs because laws are typically invoked under specific circumstances and because they guide the development of the state institutions of which they are a part.
The hard work, then, seems to have already been done in answering the question of whether rules can be considered cultural genotypes. It would be almost trivial to map Hodgson and Knudsen's argument onto Ostrom's formal conception of institutional rules. For now I'd feel comfortable concluding that rules, like laws, could be considered conditional replicators. A question that remains unanswered in my mind is what would be the cultural "phenotype" associated with rules. In other words, what is the interactor that rules respond to? An even bigger question, though, is so what? If rules are generative replicators, then what are the implications for research or policy development? In what ways might this formulation of rules provide new insights or help to organize existing knowledge? These, too, were questions that didn't get addressed at the workshop and I think they are perhaps the most important questions of all.
Yet another concept map
It seems these are always hopelessly flawed. Nevertheless, this map seems to capture most of what we've been talking about. How useful it may be is another question entirely.
So, here I've partitioned the environment into different aspects, those that affect groups and those that affect individuals. These, however, are not compartmentalized which is my way of attempting to show these are not always separate. As I've been discussing, then, groups and individuals may have very different experiences within the environment and, as a result, may face different kinds of pressures. The environment alone, however, is not the only source of influence/pressure/constraints/whatever. Groups can also exert pressures on individuals and, of course, groups are affected by the traits of the individuals who comprise them. All of these different influences work to produce outcomes. Outcomes at the group level might be different from outcomes at the individual level. Or they might not. Perhaps I should have placed them in a box together the way I did for environmental influences?
I haven't quite unpacked this yet, but it may be in the outcomes that we find some traction with our conceptions of "alignment" between groups and individuals.
Does this do any useful conceptual work? Again, I'm not entirely sure. However, it does allow us to more methodically follow constraints and pressures (are these different?) to see how they might affect tightness or looseness. For instance, let's imagine a harsh environment that offers little existential security for either groups or individuals. This would limit the variation between groups operating within that environment and between individuals who are potential members of groups. These should work together to create very tight groups.
Or what about an environment that is existentially secure for individuals but in which groups face existential insecurity by virtue, say, of fierce competition with other groups. In this environment, groups should be far looser than in the previous scenario. Nevertheless, they should be relatively tight in those particular traits that lead to differential success for the group. For instance, let's suppose that successful groups within a given context are those with the greatest perceived entertainment value. If groups can only survive by virtue of their entertainment value, then opinions about the relative importance of entertainment among group members should be tight even while opinions about other aspects of the group might be quite loose. Clearly, I need to think of better examples but hopefully this gives an idea of what we're after.
One thing I do like about this map is that unlike some of my other recent formulations this provides space to consider the bottom up influence of individuals on the group and the top down influence of the group on individuals. Aside from giving us a place to stick psychological variables like personal need for structure and social dominance orientation, it also gives us a way to consider historical trajectories. For instance, if a tight group has survived several generations of individuals then it seems likely individuals raised within the group should have a higher need for structure or a higher social dominance orientation by virtue of their indoctrination over generations by the group. Even if that group moves to a place where existential security at both the individual and group levels would lead us to predict greater looseness, it may take considerable time for the group to move in that direction due to to the bottom up influence of many tight individuals working in concert.
Okay, now I'm just rambling. Enough!
So, here I've partitioned the environment into different aspects, those that affect groups and those that affect individuals. These, however, are not compartmentalized which is my way of attempting to show these are not always separate. As I've been discussing, then, groups and individuals may have very different experiences within the environment and, as a result, may face different kinds of pressures. The environment alone, however, is not the only source of influence/pressure/constraints/whatever. Groups can also exert pressures on individuals and, of course, groups are affected by the traits of the individuals who comprise them. All of these different influences work to produce outcomes. Outcomes at the group level might be different from outcomes at the individual level. Or they might not. Perhaps I should have placed them in a box together the way I did for environmental influences?
I haven't quite unpacked this yet, but it may be in the outcomes that we find some traction with our conceptions of "alignment" between groups and individuals.
Does this do any useful conceptual work? Again, I'm not entirely sure. However, it does allow us to more methodically follow constraints and pressures (are these different?) to see how they might affect tightness or looseness. For instance, let's imagine a harsh environment that offers little existential security for either groups or individuals. This would limit the variation between groups operating within that environment and between individuals who are potential members of groups. These should work together to create very tight groups.
Or what about an environment that is existentially secure for individuals but in which groups face existential insecurity by virtue, say, of fierce competition with other groups. In this environment, groups should be far looser than in the previous scenario. Nevertheless, they should be relatively tight in those particular traits that lead to differential success for the group. For instance, let's suppose that successful groups within a given context are those with the greatest perceived entertainment value. If groups can only survive by virtue of their entertainment value, then opinions about the relative importance of entertainment among group members should be tight even while opinions about other aspects of the group might be quite loose. Clearly, I need to think of better examples but hopefully this gives an idea of what we're after.
One thing I do like about this map is that unlike some of my other recent formulations this provides space to consider the bottom up influence of individuals on the group and the top down influence of the group on individuals. Aside from giving us a place to stick psychological variables like personal need for structure and social dominance orientation, it also gives us a way to consider historical trajectories. For instance, if a tight group has survived several generations of individuals then it seems likely individuals raised within the group should have a higher need for structure or a higher social dominance orientation by virtue of their indoctrination over generations by the group. Even if that group moves to a place where existential security at both the individual and group levels would lead us to predict greater looseness, it may take considerable time for the group to move in that direction due to to the bottom up influence of many tight individuals working in concert.
Okay, now I'm just rambling. Enough!
Saturday, April 21, 2012
Selection
Tonight in an email exchange with Ian, the subject of selection came up. Or perhaps more accurately, the problem of defining selection pressure came up. Over the past couple of entries, I've been excited about thinking of group tightness and looseness as responses to differential selection pressures acting at the group and individual levels. There is something intuitive about the idea that just "seems right." As is so often the case, though, translating that gut intuition into something meaningful and practical is proving more difficult.
One stumbling block in this is that the entire scheme relies on understanding selection pressures that might act on either the group or the individuals comprising the group. But what exactly do we mean by this? How can we operationalize it? How can we measure it? My tack so far has been to come up with as many examples as I can of different groups falling into different categories of tightness and looseness and to think about the selection pressures at work. While this has been seductive, I've started uncovering examples where the whole scheme seems to break down. These have been instructive, though, inasmuch as they haven't been able to completely refute the scheme; they've left some room for the overarching idea to still wiggle free. It's in this ambiguous space that I've come to appreciate where more precision is required.
I think one place to begin is to define what we mean by selection. Without a firm conception of selection, any talk of selection pressure become rather silly. I'd like to have a more exhaustive inventory of accepted definitions, but it's already past my bedtime so for now I'll just share the definition given by Hodgson and Knudsen in Darwin's Conjecture:
Selection in a complex population system involves an anterior set of entities that is somehow being transformed into a posterior set, where all members of the posterior set are sufficiently similar to some members of the anterior set, and where the resulting frequencies of posterior entities are correlated positively and causally with their fitness in the environmental context. The transformation from the anterior to the posterior set is caused by the entities' interaction within a particular environment. (pp. 241-242)
Interestingly, they differentiate between two different kinds of selection: subset selection and successor selection:
Subset selection is defined as selection through one cycle of environmental interaction and elimination of entities in a population, structured so that the environmental interaction causes elimination to be differential, and where survival outcomes are correlated positively and causally with fitness in that environment.
Successor selection is defined as selection through one cycle of replication, variation, and environmental interaction, which leads to differential replication, novel entities, and a changed distribution of population properties that correlates positively and causally with the fitness of entities in that environment. (p. 242)
Fitness plays a role in all of these definitions, so it's probably a good idea to pin what they mean by that down, too. This turns out to be a bit thornier than you might expect:
In biology, fitness is most usefully defined as the propensity of a genotype to produce offspring (DeJong 1994). Survival of the fittest is no longer a tautology: it is possibly false. The fitness of a replicator is the propensity to increase its frequency (relative to other replicators). In the social domain, this definition of fitness translates into the propensity of a social replicator (such as a habit or a routine) with a particular feature to produce copies and increase the frequency of similar replicators in the population. The fitness of an interactor is the propensity of its replicators to increase their frequency. (p. 238)
Here I sense some slippage between these concepts. Much, I'm sure, to Ian's delight Hodgson and Knudssen define selection in terms of elimination of entities due to their interactions with the environment. However, their notion of fitness seems to be more in line with conceptions of selection for entities. Perhaps that's neither here nor there, but it is curious to note all the same.
So what to make of these definitions? At this point, I'm not entirely sure. More than anything, I just wanted to get them out there for us to begin playing with. However, some preliminary thoughts are that if we define selection in a similar way, then selection and existential security are in many ways interchangeable. Selection pressure, which oddly isn't defined at all by Hodgson and Knudsen, would seem to be a property of the environment which affects how much variation can be present within a given population interacting within a particular environmental context. If this is so, then it would seem to be even more directly related to notions of tightness and looseness than I first thought. At the very least, it's not hard to see how I could come to the idea that selection pressures are key to understanding these phenomena.
One stumbling block in this is that the entire scheme relies on understanding selection pressures that might act on either the group or the individuals comprising the group. But what exactly do we mean by this? How can we operationalize it? How can we measure it? My tack so far has been to come up with as many examples as I can of different groups falling into different categories of tightness and looseness and to think about the selection pressures at work. While this has been seductive, I've started uncovering examples where the whole scheme seems to break down. These have been instructive, though, inasmuch as they haven't been able to completely refute the scheme; they've left some room for the overarching idea to still wiggle free. It's in this ambiguous space that I've come to appreciate where more precision is required.
I think one place to begin is to define what we mean by selection. Without a firm conception of selection, any talk of selection pressure become rather silly. I'd like to have a more exhaustive inventory of accepted definitions, but it's already past my bedtime so for now I'll just share the definition given by Hodgson and Knudsen in Darwin's Conjecture:
Selection in a complex population system involves an anterior set of entities that is somehow being transformed into a posterior set, where all members of the posterior set are sufficiently similar to some members of the anterior set, and where the resulting frequencies of posterior entities are correlated positively and causally with their fitness in the environmental context. The transformation from the anterior to the posterior set is caused by the entities' interaction within a particular environment. (pp. 241-242)
Interestingly, they differentiate between two different kinds of selection: subset selection and successor selection:
Subset selection is defined as selection through one cycle of environmental interaction and elimination of entities in a population, structured so that the environmental interaction causes elimination to be differential, and where survival outcomes are correlated positively and causally with fitness in that environment.
Successor selection is defined as selection through one cycle of replication, variation, and environmental interaction, which leads to differential replication, novel entities, and a changed distribution of population properties that correlates positively and causally with the fitness of entities in that environment. (p. 242)
Fitness plays a role in all of these definitions, so it's probably a good idea to pin what they mean by that down, too. This turns out to be a bit thornier than you might expect:
In biology, fitness is most usefully defined as the propensity of a genotype to produce offspring (DeJong 1994). Survival of the fittest is no longer a tautology: it is possibly false. The fitness of a replicator is the propensity to increase its frequency (relative to other replicators). In the social domain, this definition of fitness translates into the propensity of a social replicator (such as a habit or a routine) with a particular feature to produce copies and increase the frequency of similar replicators in the population. The fitness of an interactor is the propensity of its replicators to increase their frequency. (p. 238)
Here I sense some slippage between these concepts. Much, I'm sure, to Ian's delight Hodgson and Knudssen define selection in terms of elimination of entities due to their interactions with the environment. However, their notion of fitness seems to be more in line with conceptions of selection for entities. Perhaps that's neither here nor there, but it is curious to note all the same.
So what to make of these definitions? At this point, I'm not entirely sure. More than anything, I just wanted to get them out there for us to begin playing with. However, some preliminary thoughts are that if we define selection in a similar way, then selection and existential security are in many ways interchangeable. Selection pressure, which oddly isn't defined at all by Hodgson and Knudsen, would seem to be a property of the environment which affects how much variation can be present within a given population interacting within a particular environmental context. If this is so, then it would seem to be even more directly related to notions of tightness and looseness than I first thought. At the very least, it's not hard to see how I could come to the idea that selection pressures are key to understanding these phenomena.
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