Chapter Five
HIERARCHY AND CONTEXT
* * *
5.1 From percept to proposition
5.2 The case for hierarchy
5.3 The case for context
5.4 Developmental foundationalism
* * *
5.1
From percept to proposition
Aquinas asked "Whether the Knowledge of God is the Cause of Things?"
and gave us two options. On the one
hand, "[t]he knowable thing is prior to knowledge, as the Philosopher
says." But since "what is
posterior and measured cannot be a cause," it follows that "the
knowledge of God is not the cause of things." On the contrary hand, "Augustine says, Not because they are,
does God know all creatures spiritual and temporal, but because he knows them,
therefore they are."[1]
As a good Christian, Aquinas sided with Augustine on this one, against the pagan
Aristotle. But he put before us two
fundamental options. One can hold that
what is, is what it is independently of any being's knowledge of it, and that
what is sets the terms for what counts as knowledge. Or one can hold, in either secular or divine form, that esse est percipi, and that therefore the
knowing subject ultimately sets the terms for what counts as knowledge.
In this context Aquinas advocated only the ontological side — the view that
mind has ontological priority over matter.
Setting the stage for the modern period in philosophy, Descartes
introduced the epistemological version in his second Meditation — the view that the subject is known prior to and better
than external reality. In his famous
discussion of the wax he asks,
What
am I to say in regard to this I which seems to apprehend this piece of wax so
distinctly? Do I not know myself much
more truly and much more certainly, and also much more distinctly and
evidently, than I do the wax? For if I
judge that the wax is or exists because I see it, evidently it follows, with
yet greater evidence that I myself am or exist, inasmuch as I am thus seeing
it.[2]
Epistemological subjectivism is the view that the subject has fundamental
priority in setting the terms for what is knowledge. I think epistemological subjectivism is at the root of the
positions that I have been fighting throughout this essay, and my sympathies,
to paint broad historical strokes, are squarely with Aristotle. On specific issues I have rejected
arguments intended to necessitate the adoption of subjectivist conclusions —
the conclusions that dictate that one has to start "inside" and
either set out on a quest for a mysterious correspondence-to-fact relation or
reject such a quest as hopeless and remain stuck "inside." The skeptic's Evil Demon argument, the
arguments from illusion and perceptual relativity, the arguments for perceptual
inferentialism and the theory-ladenness of perception would, if any one of them
were sound, force at least a minimal version of subjectivist epistemology. In rejecting these arguments in turn, I have
hopefully left myself in a position to advocate the fundamental objectivity of
justification and knowledge.
The results of Chapters 3 and 4, if sound, make possible the following claims
about perception.
1. Perceptual states are direct relations
between subject and object, not states that put subjects in an indirect
relation to objects.
2. Perceptual states are independent of
conceptual states, though not isolated from them.
3. Perceptual constancies are the result of
physiological, not inferential, integration.
4. Perceptual focus or attention is an
autonomous capacity, though it can also be conceptually guided.
5. Perceptual states, though not conceptual or
propositional, are cognitive states.
Our perceptual
faculties, on this view, give us a great deal of information — good information
— about reality.[3] Without representationalist or skeptical
worries we can proceed, as people do, as direct realists.[4] The procedure then is, in outline,
straightforward. In the course of
learning a language, individuals conceptualize some of their perceptual states;
in the course of learning a grammar, they integrate the resulting concepts into
propositions; and, in the course of learning logic, they integrate the
propositions into networks. Each of
these issues involves many complexities, and to the first two —
conceptualization and grammar — I will not do justice here.
As mentioned above, I accept an abstraction account of concepts, one that is
neither realist in the Platonic or Thomistic sense nor nominalist nor
Kantian. Concepts are not what make
possible perceptual discriminations, contrary to Kantian theories; they are not
merely linguistic labels attached to sets of perceptual experiences, contrary
to nominalist theories; and they are not intuited abstract essences, contrary
to traditional conceptual realist theories.[5] Concepts are reformulations of the data
given in perceptual discriminations about entities, their properties, actions,
and relationships. They require
transforming a wealth of perceptual information into more economical
units. They are, to speak loosely,
"mental space-savers" that result from an ability to
"chunk" information from many percepts into a single cognitive
unit.
The above paragraph is simply a statement of conclusions, not an argument for
them. So my account needs supplementing
by an account of concept-formation and a general defense of the conceptual
level of functioning. These are beyond
my scope here, so I will simply borrow a line and claim that the soul is
constituted such that it is capable of performing these operations,[6]
and skip over the details to issues of propositions and relationships between
them, and between them and perceptual experiences.
A proposition is a grammatically structured string of concepts. I think our concepts can be grouped into
four main categories: entities (dog, flower, blanket), actions/processes (run,
cry, eat), properties/states of entities (pink, soft, warm), and relationships
(beside, larger than, behind). A
proposition asserts a relationship between two or more concepts. Each concept is a condensation of
information about some entity, action/process, property, or relationship, so
justifying a proposition on the basis of perceptual experience means grasping
that the relationship between concepts asserted in the proposition is given in
some perceptual experience(s). At this
basic level, the temporal order of the process is: one perceives a certain relationship,
forms or calls upon the appropriate concepts, and grammatically integrates
those concepts into a single unit — a proposition. The perceptual experience thus justifies the proposition. Justification, on realist grounds, means
having a connection to fact. Perception
has such a connection, since it is a direct experiential relation to fact, so
it has what the proposition needs.
So far we have discussed only what I call type A propositions. These are propositions that identify what is
given in single perceptual experiences — for example, "The cat
jumps," "My tummy hurts," "The bird is flying,"
"The dog is furry," "Daddy is beside Mommy." Type A propositions are the
foundationalist's "basic" propositions, and the claim is that all
other propositions are derived from type A propositions. Two other, relatively straightforward,
types of propositions should be mentioned in this context, in order to get us
up to a level of propositional complexity appropriate for introducing
criticisms.
Type B propositions are generalizations and summaries from type A propositions
— for example, "Dogs are furry," "Birds fly," and
"Sometimes cats jump." The
processes of generalization and summary require the integration of several type
A propositions; part of inductive logic deals with better and worse methods of
performing such integrations. Then,
once one has formed some type B propositions, one can perform categorical
syllogisms, which are structures of either type B propositions alone or a
combination of type A and B propositions.
This, of course, is part of deductive logic.
Type C propositions are compound propositions, formed by relating propositions
of type A and/or type B by means of the connectives — for example, "If the
cat jumps, then the bird flies" and "Either my tummy hurts or I'm
imagining things." Then various
combinations of propositions of types A, B, and C can yield further
propositions; the combinations involved here are those standard forms of
deductive argument studied in propositional calculus.
We have reached a certain level of complexity here, although much more needs to
be said for a full theory of propositions: we have not, for instance, mentioned
tense, metaphor, or counterfactuals.
Indeed, as Rorty and others have stated forcefully, it is not at the
level of propositions such as "The cat is on the mat" that accounts
such as the above run into trouble, but rather at the level of propositions
such as "Love makes the world go around" and "History is the
story of class struggle."[7] When we get to highly theoretical
propositions and propositions embedded in complex networks of other
propositions, the question is whether a hierarchy and correspondence account of
justification along the lines sketched above can be maintained, or whether the
complex networking ultimately destroys the hierarchical structure of
justification the foundationalist needs to maintain.
5.2
The case for hierarchy
The need for justification is based on the fact that at the conceptual level
errors are possible. Perceptual states
are direct relations of subject and object, but in conceptually processing
their perceptual states human cognizers do not automatically get things
right. Truth, on realist accounts,
means correspondence of belief to fact.
But if a subject's cognitive processes can reach either truth or
falsity, then special efforts must be made to maintain correspondence. As adults we identify those cognitive
processes that maintain the correspondence.
Those that maintain the tie to reality are called "truth-preserving
processes," and they are distinguished from those cognitive processes that
do not. The concept of justification
pertains to the extent to which the subject follows truth-preserving processes. By identifying the cognitive processes used to
reach a given belief and comparing them to our list of truth-preserving
processes, we have an explicit measure of the degree of justification of the
belief.
When we investigate propositional truth-preserving processes, they seem to have
two dimensions. One dimension pertains
to the fact that the justified proposition depends on the justifying
proposition(s), but not vice versa. If
I believe "q" because I
believe "If p then q" and "p", then there is an asymmetrical dependence involved. The same point holds if I believe "All w are z" because I saw and identified one hundred w's in various situations and each was z.
Let's call this the hierarchy dimension: propositions are organized in
asymmetrical hierarchies of dependence.
The other dimension pertains to the fact that justified propositions are
always integrated into the wider context of one's entire system of
propositions. Any new proposition that
contradicts the rest of the system is not justified. The new proposition or the rest of the system may have to be
rejected, but the new proposition is not justified until the conflict is
resolved. Let's call this the
contextual dimension: propositions are not held in isolation from each other.
The hierarchical dimension is the focus of this section, though we will, in the
next section, return to the more difficult contextual dimension.
Broadly speaking, cognition is a process of hierarchical integration from
start to finish. Sensations are
integrated into percepts, percepts are integrated into concepts, concepts are
integrated into propositions, propositions are integrated into arguments, and
arguments are integrated into theories.
And looking backwards, from the perspective of the order of dependence,
theories depend upon arguments, arguments depend upon propositions, propositions
depend upon concepts, concepts depend upon percepts, and percepts depend upon
sensations. The dependence is
asymmetrical, which is what the foundationalist's hierarchy condition
claims. In Chapters 3 and 4 we investigated
sensation and perception; so it is now the hierarchical features of concepts
and propositions that concern us.
The case for the hierarchical structure of justification starts with the claim
that there is a necessary hierarchy of concepts. There is generally a difference in the order of acquisition of
concepts and the order of scientific organization of concepts, but the same
hierarchical principles apply. If it
is true that there is a necessary conceptual hierarchy, then since what propositions
one can form depends upon what concepts one has available, propositional
structure will depend upon conceptual structure.
To see the necessity of conceptual hierarchies, let's imagine a few cases in
which we violate it in the order of acquisition.
Suppose I walk into a scientist's lab, hoping to learn some new things. I point to a large metallic contraption
sitting on a table and ask what it is.
"It's a scientific instrument," responds my scientist. I ask about a tiny, fragile-looking glass
object; "That's a scientific instrument," says the scientist. I point to a wood and plastic object leaning
against a wall; "Scientific instrument," intones the scientist. And so on.
Clearly, given information at this level of abstraction in the
hierarchy, I'm not learning anything, and will not.
The problem can work the other way.
Suppose I walk into the neighboring laboratory and see various
containers of liquids sitting around. I
ask the scientist, "What's this?", pointing to one container. "Diexel Thombon," says the
scientist. I point to another;
"That's Biddle Mun Adonee," she replies. I make one last attempt, point to a different container, and hear
in response the word, "Granveerenze." Again, I have really learned nothing.
Or suppose that a child points to a chair, indicating that she wants to know
what it is; the parent replies "Artifact." The child points to a plastic play hammer, and the parent says,
"Artifact." The child points
to an automobile, and the parent replies, "Artifact." If this procedure continues, then
cognitively the child is not going to progress far.
As a point of structural necessity, concepts such as "scientific
instrument" and "artifact" must come later. Why?
Because one must start with what's available to the person in terms of
the phenomena the person's prior learning and/or perceptual faculties can
discriminate. The operative question
is, What differences and similarities of the entities in the person's cognitive
field can he or she attend to?
If, for example, it is the case that the child's cognitive context is such that
she can more readily notice the differences between the play hammer and the
chair and the automobile than she can notice their similarities, then the
concept "artifact" will be both unintelligible and useless to
her. The starting level of concepts
must be keyed to the level of phenomena her perceptual faculties are able to
discriminate, just as the scientist's introduction of technical terminology to
me must be keyed to the level my previous learning has brought me to.
Yet within a given level there are options, due to the differences in
individuals' environments. There exists
a degree of variability from individual to individual as to what is the content
of his or her perceptual world; hence there is some variability from individual
to individual as to what concepts will be formed first and what perceptual
judgments will basic. The difference
between being a city kid and being a country kid, for example, may mean that
one arrives at the concept "animal" after first acquiring
"dog," squirrel," and "cat" rather than after
"cow," "horse," and "groundhog."
At the level of more abstract concepts, the hierarchical order is maintained,
although again within the level there will be options and variability. Take for example the moderately
sophisticated concept "mammal."
Forming the concept "mammal" depends on a prior grasp of
certain other concepts. At a minimum,
someone needs concepts for at least one of the distinguishing characteristics
of mammals, i.e., "hair" and "milk-producing." In virtually all cases it requires some from
the following set of species that are mammals (e.g., humans, dogs, squirrels,
lions, raccoons), and one or more from the set of contrast (non-mammal) species
(e.g., fish, snakes, spiders).[8]
Conceptual knowledge is expressed and retained propositionally. At the propositional level, what
propositions are justifiable for the subject depends upon what concepts he or
she has formed. The justification of a
proposition presupposes at least a minimal understanding of the concepts it
integrates. So the conceptual hierarchy
will to some extent be carried over to propositions. Yet at the level of proposition-to-proposition justification the
primary hierarchical factor is the logic of justification. Whatever basic propositions one forms, once
one is at the propositional level there are necessary relations of asymmetrical
dependence: Some propositions are premises and some are conclusions drawn from
them. These conclusions regularly
become, in turn, premises from which further conclusions are drawn, and so on
up the hierarchy.
For example, consider the proposition "It is cheaper to ship goods from
Philadelphia to New York than it is to ship goods from Boston to New York." The justification of this proposition will
depend, at least in part, on the proposition "Philadelphia is closer to
New York than is Boston." The
justification of the proposition "Philadelphia is closer to New York than
is Boston" depends necessarily on the propositions: "Philadelphia is
distance X from New York,"
"Boston is distance Y from New
York," and "X is less than
Y." The justification of "Boston is distance Y from New York" will require a
whole raft of previous propositions — "This is a ruler," "This
is a map," "New York is shown on this map," "Boston is
shown on this map," and so on.
Each of these propositions depends on certain conceptual distinctions,
each of which ultimately depends on perceptual phenomena. In this example, "Boston is distance Y from New York" is at least two
stages away from perceptual experience, while "It is cheaper to ship goods
from Philadelphia to New York than it is to ship goods from Boston to New
York" is at least four stages away.
The above is a highly simplified example, but it illustrates the point that
there is a hierarchy. Not all
propositions are at the same level in the hierarchy, as measured by the
distance from perceptual phenomena.
5.3
The case for context
While justification exhibits a hierachical dimension from the outset, it also
exhibits a contextual dimension. Our
perceptual faculties are limited; in any given time frame one can perceive only
so much. When forming a concept of a
perceptual object, such as "dog" or "ball," one has a limited number of perceptual
experiences, both current and remembered, to draw upon. This sets a context: a background framework
that delimits the concept's breadth and depth.
As one's perceptual experiences change — one can get new angles on the
phenomenon, or a broader acquaintance with phenomena of that and related sorts
— one's concept is revised. The
revisions can involve the concept's becoming broader or more detailed, for
example. When forming increasingly
abstract concepts, the point holds again: one has a limited number of
previously-formed concepts to draw upon.
These previously-formed concepts set the context for the new one. But the new one may become revised in the
light of other concepts, either new or revised ones, as we shall see below.
At the level of propositions, propositional meaning
is conditioned by context. If one
walked in at the end of a political speech and heard the speaker proclaim
"And therefore I proudly proclaim my commitment to the principle of the
right to life!" — without any background context, one wouldn't know what
the speaker means, let alone whether one agrees with the speaker. Whether the speaker favors the view that
each individual's life is his or hers to make the most of, or the view that
every individual is automatically entitled to sustenance from all the other
members of the society, or the view that abortion is wrong under any
circumstances — is contextually conditioned by what was said earlier in the
speech. That proposition has the
meaning it does due to its place in the structure of propositions that makes
up the speech.
Propositional justification is also
conditioned by context. For any
proposition, its justification depends upon two contextual elements: the
conceptual hierarchy it is embedded in, and the propositional hierarchy it is
embedded in.
To illustrate the relationship of conceptual context to propositional
justification, let us take as an example the proposition "Airplanes
fly." This is a justified
proposition for most of us: we each have ample perceptual evidence of having
seen airplanes flying overhead or having ridden in them. But this is not the whole story. One is operating on a certain definition of
"flying" — say, "self-propelled motion through air." Perhaps one's concept of flying was formed
in contrast to gliding and to being thrown.
It may also have been formed in contrast to swimming, which is
self-propelled motion through water, and to walking, which is self-propelled
motion on the ground. One's concept of
flying is also formed and held in context of one's knowledge of birds: one
knows that birds also fly. All of this
is perfectly reasonable, and all of it forms the background context to one's
justified belief that airplanes fly.
Now suppose that some scientists investigate the actions of penguins when they
propel themselves through water and come to the conclusion that what the
penguins are doing is flying and not swimming.
The dynamics of the penguins' action, they discover, are exactly the
same as those of birds flying through the air, and the actions of birds moving
through the air and penguins moving through the water are both very different
from the characteristic actions of fish when swimming. If one hears of this new information, one
then has to reevaluate the essentials of flying — which means one has to
reevaluate one's concept "flying."
And since the proposition "Airplanes fly" depends upon a
specific characterization of flying, a reevaluation of one of the
proposition's constituent concepts certainly bears upon the justification of
the overall proposition. One may decide
that the medium through which one moves is inessential to flying, so one will
drop the phrase "through air" from one's list of the essentials of
flying. One may also decide that the distinctive
type of self-propelled action that penguins and other birds both perform is
fundamentally different from the type of self-propelled action that airplanes
do, and that, accordingly, the concept "flying" is not technically
appropriate for describing what airplanes do.
One might then say that airplanes thrust
themselves through the air, and that to say that airplanes fly is a metaphorical extension of the concept.
The point is that new information can force a restructuring of one's
conceptual hierarchy (in this case, in the direction of greater precision),
which forces a reevaluation of the justification of the propositions built
from those concepts. Since no concept
is an island in the hierarchy, adjusting any given concept has effects on other
concepts in the hierarchy, which also has effects on the propositions that
depend on those concepts. This in turn
means that propositions cannot be justified in a way that is immune from any
future conceptual revisions. Justification
is a conceptually contextual issue.
Justification is also a propositionally contextual issue. Not even type A propositions (i.e., those
that conceptually identify perceptual level phenomena) are justified completely
and forever out of any context. One may
see a woman's dress and judge that at it is magenta. But then one may be told that the lighting is more blue than
white and so become — and properly so — less inclined to believe that her
dress is magenta. Other propositions
can be relevant to the justification of even so basic a perceptual judgment as
that of color.
Any proposition other than a type A proposition depends upon inductive support
from a number of other propositions.[9] As new information comes to light, one's
cognitive context changes, and the degree of justification for relevant
propositions may be changed. Consider a
typical example.[10]
Suppose one gets into one's car with a friend on a winter's evening, inserts
the key into the ignition and turns it — but the car fails to start. Not only does the car fail to start, the
engine doesn't even turn over. Now,
from one's previous experience, one inductively infers that the battery is
probably dead. Depending upon the range
of one's experience, believing the proposition, "The battery is
dead," will be justified for one to a given degree. That degree of justification can
change. Suppose one's friend points out
that a new battery was installed just last week. Taking this new information into account lessens the degree of
justification of "The battery is dead." But then one remembers that the battery was installed by a
drunken mechanic; the degree of justification of "The battery is
dead" increases. But then one's
friend says that he checked the installation of the battery afterwards and
noted that everything was fine; the degree of justification again goes
down. And so on. To bring the story to an end, suppose one
finally notices that the car's light switch was left in the "On"
position; then "The battery is dead" becomes highly justified for
one.
The point is that propositional justification is contextual. Contexts change: new information can come to
light that necessitates either a revision of one's conceptual hierarchy or of
one's assessment of the degree of inductive support. This means justification requires that one remain open to new
evidence, pro or con, and that one be willing to revise or reject previously
justified propositions.
The question then is: Are such facts inimical to foundationalism?
5.4
Developmental foundationalism[11]
Initially there seems to be no problem reconciling the two dimensions of
justification. Acquiring knowledge is a
process of discrimination and integration: one first discriminates an item and
then integrates it with the rest of one's beliefs. For example, one distinguishes something perceptually; then one
identifies it conceptually, thus integrating that percept with the rest of
one's knowledge. There is both a
hierarchical element (one's perceptual awareness of reality's validating the
proposition) and a contextual element (one's previous conceptual knowledge's
placing the new item within the context of one's entire body of beliefs). Or it may be that contextual elements
enhance the justification of two bodies of propositions further up the
hierarchy. Suppose one has two
different hypotheses, supported to a certain extent by perceptual
evidence. If one finds that they
complement each other and integrate a wider body of evidence than either can do
on its own, this lends some support to each.
This is like finding that two separate parts of a jigsaw puzzle, which
one has worked on independently, fit together perfectly. How could such "coherence"
phenomena be a problem? One strives for
an integrated system of propositions, each of which is ultimately derived from
perceptual evidence.
The problem seems to be the worry that the contextual dimension collapses the
hierarchy dimension. The problem comes
in two forms, one from the perspective of traditional foundationalism and one
from the perspective of the coherence theorist. From the standpoint of traditional foundationalism, the
contextual dimension is problematic, for it opens up the possibility of
revisions. Yet the whole point of
traditional foundationalism's insistence upon hierarchy is to trace justificatory
connections back to incorrigibly known propositions, and then to build
inexorably from there. But if
everything is potentially open to revision, then one has no absolute,
contextless certainty for any of one's propositions and thus no haven from
skepticism.[12] If, however, we reject traditional
foundationalism's concern with skepticism (as in Chapter 3) and its attendant
quest for contextless certainty, then the possibility of revisions need not be
a problem for foundationalism on that ground.
As long as justification still exhibits a hierarchical structure, and
as long as that structure is grounded in perceptual data, revision and
reorganization among one's concepts and propositions are compatible with
foundationalism. It is exactly here
that the coherence theorist sees problems.
As the coherence theorist points out, the contextual dimension of justification
means that one's system of beliefs is (or should be) an integrated whole. As such, revisions in one part of the system
cannot help but have "ripple" effects upon the rest of the system;
the system faces revisions as a whole.
Yet as adults, our belief systems are incredibly huge. The ensuing problem, from the perspective of
the coherence theorist, is that the system is too huge for anyone to follow all
of the "ripples" back to perceptual roots in order to determine
whether the system is properly grounded.
If each proposition were an acontextual island, then checking
correspondence to fact would be straightforward. But since each proposition is not an island, it seems that the
contextual dimension means the foundational hierarchy dimension is lost. One can only trace the "ripples"
so far, and this means, as Neurath suggests, that the entire system has to
float: each cognizer is like a sailor "who, unable to return to dock,
must reconstruct his vessel on the open sea, and is therefore forced to make
use of the best constituents that are at hand."[13] One is unable to "return to dock"
because it seems that to accomplish that one would either have to be able to
trace an indefinite number of justificatory connections at a moment (follow all
of the "ripples") or be able to take a perspective from somewhere
outside the whole system in order to compare it to reality. Neither of these can one do.
Everything is right about this argument except the conclusion. It is certainly true that working through
the implications of a revision can be a lot of work, especially as one's belief
system becomes both more wide-ranging and more specialized. But there's no getting around this: an
inconsistent set of propositions is not justified. And one needs to keep open the possibility of revisions precisely
because one's system of beliefs is so huge.
From a limited context it is extremely difficult to form a hypothesis
that takes into account all factors.
The common case is that new evidence arrives that brings to light new
factors that either necessitate qualifications or rejections of old hypotheses. Or in attempting to integrate two
well-grounded hypotheses in related fields, one may discover inconsistencies
that necessitate revisions to one or both of the hypotheses.
And justification requires a tie to reality.
Justification is a necessary condition for knowledge, and knowledge is
about reality. Direct access to reality
is given only in perceptual experience.
So justification requires a connection to perceptual experience. In other words: the goal is truth, truth depends
upon correspondence to reality, and justification is the process of establishing
correspondence. So there's no getting
around the need to trace the ripples and there's no getting around the need to
connect the propositions to perceptual evidence.
The question, then, is how much justificatory work revisions involve, and the answer
seems to be a straightforward, "It depends." This is a huge topic, but the amount of work
involved seems to depend upon (1) how radical the initial revision is and (2)
where in the system of one's propositions it occurs.
On (1), changes that force revisions come in degrees. Depending upon the degree, the ensuing system-wide revisions
will be more or less radical. For
example the change from a Ptolemaic to a Copernican astronomy is more radical
than the change from a Copernican to a Keplerian astronomy. Similarly, the change from an immutability
view of biological species to a Darwinian evolutionary account is more radical
than a change from a Lamarckian to a Darwinian version of evolution. Accordingly, in the former cases the
revisions will necessarily be systematically more wide-ranging, while in that
latter cases the revisions will be more limited in scope. In the former cases there will be radical
abandonments of one set of concepts for another (as, for another example, in
the case of abandoning phlogiston for oxygen), while in the latter cases there
may be only slight revisions of certain concepts or the accommodation of one
framework into a larger one (as, for example, may be the case in the transition
from Newtonian to Einsteinian physics).
There is nothing necessarily easy about this: the needed revisions may
not be obvious, and the transitions may take years or generations to work
through.
On (2), the location of the initial revisions within a system of propositions
also determines the number of ripples (i.e., justificatory connections) that
need to be traced, established, or re-established. To give a straightforward example, a revision of one's views on
the trade deficit can force significant changes in one's economic opinions, but
it will not have much effect on one's views in art history or evolutionary
theory. Some legitimate degree of
compartmentalization exists within systems of propositions due to their
positions in the hierarchy, and this compartmentalization limits the system-wide
impact of revisions. This means, for
example, that our imagined revisions to one's concepts by the
"discovery" that penguins fly rather than swim will not necessarily
be some hugely indefinite project. For
such a moderately sophisticated change, only a moderate number of concepts and
propositions are affected, and for each its initially justifying perceptual
data are easily within reach. At the
other end of the spectrum, very little is left untouched by Einsteinian
physics due to its attempt to be an account of the principles governing
virtually all phenomena; as such, it has connections to virtually every other
concept and proposition. Any revision
at this level entails an enormous amount of work, but it is work that must be
done.
For all such cases, volumes need to be written. From historians of science we need detailed case studies. From philosophers we need full theories of
concept-formation and logical methodology.
And these need to be fleshed out by philosophers of science on the
technical issues of theoretical reduction and integration, principles of
taxonomic organization, and so on.
These projects will not work if we start by assuming the contextual and
hierarchical dimensions of justification are inimical to each other. What is needed instead is a developmental
account that integrates the two. This
will, as a necessary step, require a rejection of the traditional picture of
foundationalism shared in common by antifoundationalists and most
foundationalists. Traditional pictures
of foundationalist hierarchies most often speak in terms of deriving all
justified propositions from a limited number of basic propositions. The resulting picture is of an inverted
pyramid, to which monolithic blocks are added in an upwardly-expanding
direction. First we need to flip the
pyramid: at the base is an ever-expanding number of propositions. These are the basic propositions, based
directly upon perceptual experiences.
Then we have to realize that the pyramid is not really a good structural
metaphor after all, for as one ascends the hierarchy the structure expands both
upwards and outwards: depending upon what areas of investigation are pursued,
some parts of the hierarchy will be more developed than others. There is nothing static about this, as
discussed above. New perceptual
evidence will arrive necessitating and justifying new concepts and
propositions. Connections will be made
between previously separate parts of the structure. The structure will be used as a base from which new levels will
be erected. And over time the
hierarchical structure will undergo revisions at each level. Such is the history of science.
* * *
[1] Aquinas (1945, I, q.14, a.8).
[2] Descartes (1958, pp. 190-191).
[3]Vol. II, p. 93]).
[4] "Realism," as Maritain put it, "is lived by the intellect before being recognized by it" (1959, p. 79).
[5]p. 335). Price thinks this temptation should be resisted.
[6] Aristotle, Posterior Analytics (II, 19, 100a 13-14).
[7] Rorty (1980, in Moser & vander Nat [1987], p. 213).
[8]from observations of life forms native to its habitat.
[9] I am setting aside the issue of whether so-called analyt ic or a priori propositions exist, and whether they are exceptions to this rule.
[10] I am indebted to J. Michael Dunn for this example.
[11] The adjective is borrowed from a suggestion in Kelley (1986, p. 210).
[12]seen as refuting foundationalism.
[13] Quoted in Chisholm (1982, p. 13).