www.TheLogician.net © Avi Sion - all rights reserved
© Avi Sion
All rights reserved
Avi Sion, 1990 (Rev. ed. 1996) All rights reserved.
We defined logical modalities with reference to the relative
credibilities of appearances 'within contexts'. We will here try to clarify what
constitutes a context, and its role.
In a very narrow, 'logical' sense, one might refer to the context of a
proposition as any arbitrary set of propositions. In this sense, a proposition
could be taken in isolation and constitute its own context. It might still
appear to us as true (if in itself reasonable looking) or false (if obviously
internally inconsistent) or even problematic (if of uncertain meaning). Likewise
for any larger set of propositions we choose to focus on exclusively. But this
leads to a very restricted sense of truth or falsehood.
In practise, there is no such animal. A more 'epistemological'
understanding of context is called for. The effective context of any proposition
is not arbitrarily delimitable, but is a very wide body of information, which,
whether we are conscious of it or not, impinges on our judgement concerning the
proposition. It is the 'status quo' of knowledge at a given time, for a given
individual or group.
A proposition is not just a string of words or symbols written on a piece
of paper; it has to mean something to become an object of logical discussion. We
cannot consider it in isolation, because our consciousness is, like it or not,
always determined by a mass of present or remembered perceptual and conceptual
data. This periphery is bound to affect our reaction to the proposition at hand.
It is in acknowledgement of this dependency that our definitions of
logical modality must be constructed. The context of a proposition is thus all
the things we are experiencing or thinking, or remember or forgot having
experienced and thought — which happen to color the proposition at hand as
credible or not, to whatever degree.
This is not intended as a psychological observation, suggesting that our
judgment is being warped by structural or emotional factors; in some cases it
indeed is, in others not. Nor is the issue what we consciously take into
consideration; that may have no effect, and there may be unconscious influences
It is merely a recognition that the appearance of realism or unrealism of
any proposition is always a function of a great amount of data, besides it and
any artificially selected framework. The contextual data generating such a
result include: perceptions, direct conceptual insights, and indirect inductions
and deductions. Hence the concept of a context, as here used. It refers to the
actual surrounding conditions of our knowledge.
It is hard to pinpoint precisely and with unfailing accuracy just which
of the peripheral information impinges on a given proposition's evaluation.
Innumerable wordless sensations, mental images, and intuitions, are involved,
and merely having had logically relevant experiences or thoughts, does not
entail that they played any effective role in the present result. All we can say
with certitude is that a lot of data is involved in the final display of some
quality of credibility by a proposition.
The whole of logical science may be
viewed as an ongoing attempt to investigate this aetiology. Its job is to
find just what causes propositions to carry conviction or fail to do so, and how
the totality of knowledge can be gradually perfected. We have seen its work in
the domain of deduction with certain categorical propositions; now other forms
are about to be analyzed. The solution to the problem of knowledge is not found
in simplistic and vague pontifications, nor in a step-by-step linear guidebook,
but in a vast tapestry of interlocking considerations.
The concepts of truth, falsehood, and problemacy, refer to the
deployments of credibility in a static context, the 'state of affairs' in
knowledge at a given stage. The concepts of necessity, impossibility, and
contingency, refer to the changes of credibility: they consider knowledge more
Knowledge is an evolving thing. We, human beings, are none of us ever
omniscient or infallible. If our consciousness was unlimited by space, time, and
structural resources, like Gd's, there would be no problematic knowledge: every
proposition would be true or false with finality. Just as reality is one,
knowledge would be one and complete.
But reality is opened to our consciousness piecemeal, over time. We are
obliged to repeatedly adapt to new factual input. Indeed, we have to actively
dig into reality, if we want to approach that ultimate goal of total
consciousness of everything.
We know we cannot reach that goal, since we have already missed out on
enormous tracts of reality in the distant past, and the whole future is ahead of
us, unexplored. We know that innumerable phenomena are happening all around us
and within us, all the time, at every level (from the sub-atomic to the
astronomical, from the material and physiological to the mental and spiritual);
and we cannot keep track of all that. Thus, the data available to us is
Furthermore, our faculties of knowledge can play tricks on us, and draw
us away from the goal. Our eyes may be myopic, our memory may fail, our
reasoning may be muddled, we may be too imaginative, our mind may be moved by
very subjective, emotional, considerations. We have to somehow make-do, in spite
of all such imperfections in our make-up.
Our response to these limitations, if we are intent on knowing reality,
is staying aware of our mental processes, and unflagging reevaluation of what
and how much we know or ignore. This is where logical modality comes into play.
It provides us with labels we can attach to each and every proposition, which
assign it a rank, as we proceed.
Theoretically, we take the full body of everything we have experienced or
thought thus far, and order the present information in a hierarchy. Tools may be
invented to increase our certainties: eyeglasses, the written word, a science of
logic. The sources of information are considered: we distinguish between the
fictions of our imagination and the facts of sense data, between vague and clear
concepts, between fallacious and rigorous argumentation.
In practise, things are more dynamic than that. We may take some part of
our data base, and hold it still long enough to evaluate it with the proper
amount of reflection. But, on the whole, the process is on-going, an ad hoc
response to the flux of information. Logical modalities allows us to register
our value-judgments of this kind as we proceed, like a running commentary.
Now, there are three ways for knowledge to evolve, and credibility to
change. We may associate the word 'context' to the sum total of knowledge, the
whole environment — or, more restrictively, to a given body of fundamental
axioms and raw data, a framework. Here, let us use it in the latter sense.
We may not have drawn all the possible lessons from these primary givens;
the process is not automatic, but has a time dimension. A proposition may be
logically implicit in knowledge I already have, but it may take me time and
effort to discover it.
There is always a great deal of undigested, unexploited information in
our memory banks, and accessing it and assessing it demand time and skill. I
mean, Philosophy, for example, requires relatively little raw data to develop
considerably, because it pursues facts implicit in every existent. This is
internal development, or context intensifying.
Or we may receive new input of rational axioms and empirical data to
consider. Here, two alternatives exist: either the new facts already existed out
there, but unbeknown to us; or some change occurred in these external objects
themselves, which we accordingly now absorb as new existents. These are
developments fed from the outside, or context extending.
Thus, we may distinguish between three time-frames for modality change:
the external time in which objects change into new objects; the interfacial time
of turning our attention and sensors towards pre-existing objects — to extend
context; and the internal time of mental assimilation of memory (analyzing,
comparing, checking consistency) — the work of intensifying context.
The first of these essentially pertains to natural and temporal modality;
the second, extensional modality; the third, is the time-frame of logical
modality. But all of them, if only incidentally, concern logical modality.
That our definitions of truth and falsehood do not specify the context
taken as being final and ideal, is not a relativistic position. It is merely
intended as a statement that every proposition's credibility is conditioned by a
The given context is pragmatically accepted as a starting point for
further inquiry, without thereby being regarded as 'the best of all possible
contexts'. It is subject to change, to improvement. Some contexts are to be
favored over others — the exact grounds just need to be elucidated.
We might refer to the overall credibility of a context. We could perhaps
consider any given context as a whole, and (of course, very roughly) sum-up and
average the credibilities of its constituents, and thus get an estimate of its
finality or staying-power. But, quite apart from the issue of practical
feasibility, I do not think this would be of any use. The relative credibilities
given within each context pertain to that context alone, and have no bearing on
the relative credibilities in other contexts.
The general principle for comparing contexts seems obvious enough.
Contexts are of varying scope and intensity, and it is clear that the
deeper and wider the context, the closer to final will the impressions of
truth or falsehood concerning any proposition in it be; and the less numerous
will doubtful cases be. Thus, the bigger and more cohesive the context, the
The ideal context of omniscience is beyond man's power, we can only
gradually approach it. But we can say that in that ultimate, limiting case, the
impressions of truth or falsehood would be final, subject to no further change
or appeal; and furthermore, there would be no in-between impressions of a
doubtful kind, since reality once established is determinate. Here, knowledge
and reality would correspond entirely.
When we apply the above principle to one person over time, it is
relatively easy to say which context is to be preferred. The more information at
his or her disposal, the more this information has been carefully sifted for
hidden messages, the more certain may that person be. For the individual,
improvement is almost inevitable over time, because his or her context is a
We always refer to appearance, though we can distinguish between
prima-facie impressions and well-tested impressions. The two kinds of impression
are essentially the same in nature, but they have different positions in a
continuum stretching from subjectivity and mere belief (which still however
contain seeds of objectivity and knowledge) to ultimate realism and certainty.
When, however, we compare the contexts of two (or more) people, it is not
so easy to say which is better or worse. Each may have data the other lacks, and
each may have thought about any item of data they have in common more thoroughly
than the other. Thus, they may disagree in their conclusions, and yet both be
'right' for their respective contexts. And since their contexts overlap in only
some respects, so that neither embraces the other as a whole, the contexts
cannot be rated better or worse.
All we can do is focus on specific areas of knowledge, and consider the
relative expertise of each individual in that area. If someone is a specialist
in some field, we may well assign greater credibility to his or her
pronouncements on the subject. On this basis, we may even trust a person we know
to be generally very wise, without committing the fallacy of 'ad hominem'.
We must distinguish, here, between personal and social knowledge.
At the lowest level, is 'personal knowledge'. Some people are better at
knowing than others, because of their healthier faculties, or because they are
endowed with more intelligence and insight, or because they are more interested,
more careful, and make more of an effort, in this domain. Also, individuals
inevitably have different quantities of information at their disposal, both
inner and outer.
'Social knowledge' is an ideal. We collectively, across cultural
boundaries and the generations, gradually compile a record of common knowledge,
agreed upon methods, information and conclusions. It is the human heritage, our
shared data bank.
An individual may admittedly have more knowledge of some field than
everyone else at a given time; he may get to share it, or it may disappear with
him. There may be specific disagreements at any time between groups of
individuals. It may even happen that the majority of the peer group wrongly
rejects an individual's valuable contribution.
Yet, over time, the collective enterprise we call Science develops, a
pool of knowledge greater and truer than any which individuals can fully match,
based on a methodological consensus.
Since credibilities depend on context, individuals may assign different
credibilities to the same proposition. To that extent, truth and falsehood are
often 'subjective', since they reflects the mental abilities and dispositions of
Still, I may take all the premises of another person and demonstrate that
his evaluations are logically incorrect even for his context. In a sense, I
start off with the same context as him, and end up with a slightly different
version; but in another sense, I have merely clarified the given context,
brought out its full potential, without significantly altering it. If he is
intelligent and honest enough, he normally bows to the evidence.
Thus, the contextuality of credibility need not imply its utter
subjectivity. The evaluation can only ultimately be viewed as subjective in the
pejorative sense, if it is contextually wrong.
And even then, such accusation can only be leveled fairly if the
individual allowed psychological forces to sway his judgment. He may be
intellectually negligent through laziness, or dishonestly evade unpleasant or
frightening data or thoughts, or insincerely report his conclusions. If the
error was honest, merely due to a failure to notice a connection, we can hardly
criticize him, only correct him.
We get around these problems of personal weakness through the institution
of social knowledge, science. This allows us to collectively 'average-out' the
subjective vector. We mutually scrutinize and criticize each other's
contributions, until we are of one mind. There may still be collective delusion,
but that at least eliminates personal deviations from logical norms.
We presume that the influence of our collective mind-sets will gradually
wither away as knowledge develops further. This assumption is justified by
previous developments: we have seen historical examples of liberation from ideas
which seemed immovable. The notion that science is inevitably subjective, is
derived from such liberations, and cannot be used to denigrate them.