Venn, pp. 1-9 of Principles of Inductive Logic

[Matt Faunce]

The Principles of Empirical or Inductive Logic, by John Venn, pp. 1-9

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CHAPTER I.

THE FOUNDATIONS OF LOGIC:— THE UNIVERSE AS THE MATERIAL LOGICIAN REGARDS
IT.

Since Logic, as conceived and expounded in this work, is not an ultimate
science, in the sense of being concerned directly with really first
principles of any kind, we find ourselves obliged, on a general survey of
our province, to take for granted that a great deal has already been
accomplished or decided for us in various directions. In other words, we
have to demand a variety of postulates, drawn partly from the region of
Metaphysics, partly from those of Psychology, Physical Science, Grammar,
and so forth. Some of these postulates will be readily accepted by every
one : others will be admitted by those who have had any philosophic
training : some, I take it, have hardly yet been duly appreciated or even
recognized. This being so, it would seem convenient that the more important
of these postulates should be prominently and definitely stated at the
outset. For one reason or another, however, such a course seems seldom
adopted, and the result has been disadvantageous in more ways than one.
This neglect to state the postulates has, for instance, brought down upon
the logician charges of inconsistency and shortsightedness, which might as
fairly be brought against the representatives of most other sciences, but
which seemed damaging when he had to meet them alone. It has also tended,
as I shall trust to show in the sequel, to encourage mistaken views as to
the functions and province of the science; whilst the general objections to
such an omission, on the grounds of order and method, are too obvious to
need enforcement.

The reader need hardly be reminded that, in such a preliminary statement of
assumptions, we cannot fairly be called upon fully to justify them. They
would not be assumptions or postulates, if we were to undertake to do this.
We ought,

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however, to endeavour to explain their nature as clearly as possible, and
to give some kind of indication of the grounds for resorting to them, and
of those problems of our science in respect of which difficulties will be
removed by their acceptance.

I. When we claim, as the first of such postulates, the existence, and the
general recognition of external ‘ objects ’, in the widest sense of the
word, it may seem to the reader unfamiliar with philosophy as if we were
not making any assumption worth mentioning. He would be inclined to take it
for granted that these objects exist ; and that consequently all that we
have to do, so far as our logical premises are concerned, is just to open
our eyes and other organs of sense, and perceive what is before us.

The fact is however that certainly one stage, and possibly two, must have
been passed through, before the simple recommendation to observe the
objects before us can be carried out. If accepted, they are both stages of
the utmost importance; and historically, — that is, in the gradual
development of the human race, — each may have demanded an enormous time
for its accomplishment.

(1) In the first place then, in the opinion of many philosophers, the
primary stage of recognizing that 'objects’ are outside us at all, has had
somehow to be reached. They maintain that the only indubitable data of
consciousness consist in our own subjective impressions, and that
everything beyond these is inference, instinctive suggestion, illusion, or
convention of language, according as we regard it or like to express it.
This primary postulate seems to belong so completely to the domain of
Metaphysics in contradistinction from that of Logic, that we should hardly
have thought it necessary to state it here, but for the fact that much more
space than will be required thus to notice it is not unfrequently wasted
indirectly, by the introduction of discussions or quibbles arising almost
entirely out of the neglect to notice it. Refer, for instance, to Mill’s
Logic. When he is discussing his arrangement of the Categories, he throws
into two separate subdivisions, respectively, our own simple sensations and
the external objects which are supposed to give rise to these. But then he
almost immediately proceeds to disclose the fact that in his own opinion
all external objects are, in the ultimate analysis, nothing else than
states of con-

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sciousness ; and so the distinction seems to be broken down again. Not only
is this a cause of perplexity to one beginner after another, but his
arrangement has been made a serious ground of complaint by more than one
critic. He has been told that, as regards the Categories, he has no
business to distinguish ' bodies ’ from ‘ sensations ’ ; and that, in the
corresponding question as regards the Interpretation of Propositions, he
has equally no business to distinguish between propositions which deal with
‘ facts ’ and those which deal with ‘ ideas. ‘

But there is really no necessary inconsistency here, if we only bear in
mind that Logic is not an ultimate science, but stands, so to say, upon a
plane at the same depth of philosophic analysis as do the various physical
sciences. The existence of an external world, in fact, is just one of those
questions which a man must be left to settle with his metaphysician, but
which he has no reason to introduce in the case of any quarrel between
himself and his logician. He cannot utter any of the precise statements of
logic, or any of the looser ones of common life : he cannot claim to be
right upon any subject of discussion, he cannot be shown to be wrong : he
cannot even ask a question which goes outside his own private feelings :
without admitting all that we require for our present purposes. ‘ Things’,
if they were ever, at any very early epoch of our mental development,
consciously constituted by our sensations or groups of sensations, must
have already ‘ fallen back ’ from us, out of their simply subjective
condition. By direct intuition, by passive association, by some kind of
active mental construction, or by one or other of the various means which
philosophers have suggested, we must have come to contemplate the world and
to reason about it, as if it were mainly composed of things or phenomena
external to our own minds. Or, to take a simple concrete example; when I
utter the statement 'The sun is hot’: it is not relevant in Logic, however
suitable in Metaphysics, for any one to interpose the objection that the
sun is nothing but sensations of light, heat, &c. ; and that we are
therefore only connecting together two kinds of sensation, rather than an
object and a sensation. Such criticism is simply irrelevant in Logic,
nearly as much so as it would be in Physics or in Zoology. We must
postulate, at our starting-point, objects and

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our sensations, not simply two sets of sensations of which one is more
complex than the other.

Our first postulate therefore is simply the resolution to start with a
duality of existences ; — our sensations and ideas on the one hand, and the
materials or objective data which constitute the world of phenomena on the
other. As already remarked, this postulate is only required as against
certain metaphysicians, or as against critics who raise objections on
behalf of the metaphysicians which these would not always raise for
themselves. The bulk of ordinary thinkers and observers, whether scientific
or not, will freely grant the assumption, and probably only wonder at the
necessity of any such formal statement of it.

(2) But very much more than this is demanded. Detached fragments of
externality, however completely we may have thus projected them outside our
own personality, will not suffice to produce even an irregular and chaotic
world, for they will not avail to constitute the separate ‘ objects ’,
however fragmentary and disorderly these may be, with which a chaos must be
conceived to be occupied. A good deal of positive constructive effort is
demanded in order to bring into being even

“a dark
Illimitable ocean, without bound.
Without dimension; where length, breadth, and height.
And time, and place, are lost; where eldest Night
And Chaos, ancestors of Nature, hold
Eternal anarchy, amidst the noise
Of endless wars ; and by confusion stand.”

In order to constitute these warring objects a very considerable amount of
grouping, with the correlative process of distinction and separation, must
have been already accomplished. This step, unlike the one above, is a step
about the reality and necessity of which there can be no doubt, and it is
one which we can readily conceive ourselves as actually engaged in taking.
The human race, as a whole, must certainly have gone through this
continuously interchanging process of Analysis and Synthesis, and is in
fact still perpetually, though slowly, carrying it on at the present time.
And each individual of the race concurs in the carrying out of this
process, to a greater or less extent, according to the independence of his
mind, and to the keenness of his observing and discriminating faculties. Of
course most

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of us, and at most times, are almost entirely passive here. We find the
work pretty effectively done to hand for us at our birth; the instrument by
which it is thus accomplished and perpetuated for us being, it need not be
said, the language we inherit from our predecessors.

Although, however, the work is mostly found ready done for us at our birth,
we can easily put ourselves in imagination into the position of having had
to originate it for ourselves, and it is only by such a supposition that we
can realize its magnitude and importance. By devices familiar enough in
psychological discussions we can picture to ourselves a man with mature
faculties but with nascent experience; — one somewhat in the state which
Buffon has strikingly illustrated in a curious digression in his Natural
History, where he has given a brief autobiographic sketch of our first
parent’s supposed experience on his first day and night in Paradise. This
experience however mostly refers to a later stage than that to which we
might go back. It refers to such doubts as might be entertained as to
whether the sun will continue to rise and to set, and to warm and enlighten
the earth. These are most important questions, and their due consideration
will fully occupy us in the course of the next two or three chapters. What
must be insisted upon at the present moment is rather the process by which
we have come definitely to formulate such doubts. Before we can ask whether
the sun will rise and set again, we must have reached the point of
recognition , — of perception in fact , — of such objects as sun, earth,
and our bodies, and of such processes as lighting and warming.

Whatever may be said here under this head will be familiar enough to the
reader who knows something of Psychology, but it may be convenient to add a
little explanation for the use of the beginner, and to point out the
peculiar logical significance of the process in question. Even were we to
grant all that the Natural Realist would claim, viz. that the separate
elements of the various phenomena of nature have always stood out distinct
from our own personality, clearly detached from the first moment as they
seem now, yet there would not consequently be to us any ' sun ’ or ‘ earth
’ to form the subjects of even our most doubtful and interrogative
propositions, nor any ' light ’ and ' warmth ’ to form their predicates.
Select what object we

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please, — the most apparently simple in itself, and the most definitely
parted off from others that we can discover, — yet we shall find ourselves
constrained to admit that a considerable mental process had been passed
through before that object could be recognized as being an object, that is
as possessing some degree of unity and as requiring to be distinguished
from other such unities. Take one of the most obvious instances of a
persistent unity, say the sun. This has to be identified day after day, in
the East and in the West, behind cloud or haze and glaring down upon our
heads. But identification of an object under varying circumstances means
nothing else than the capacity of holding together, in a mental synthesis,
certain elements which in nature are often and widely separated; and also
of separating from each other elements which from time to time are actually
found to be conjoined. Unless this process had been adequately carried out
we might be dazzled with light, or be scorched with heat, and others might
express the actual facts and their relation to us, in the form of
propositions; but we could not be said to see or feel the sun in any other
sense than that in which one might declare of a dog, for instance, that he
perceives ‘the British character’. The ultimate constituent elements of the
perception and of the corresponding assertion are presented to the
sensitive agent, but unless he has himself grouped them aright, he cannot
be said to perceive the object.

Reference has just been made to the instance of an animal and its
perceptive powers. It is worth dwelling a little further upon this
illustration, in some familiar application. I do not ask, then, whether the
dog believes that the rainbow is a sign of good or bad weather, but raise
the previous question, whether he can be said to see the rainbow at all.
That every detail of colour and of form is painted upon his retina, as upon
ours, when the eye is turned in the right direction, is beyond all
reasonable doubt. But such an admission only carries us a very little way.
The rainbow, regarded as a visible object, consists of a group of colours
arranged in a certain shape. The outline of the red circle, say, has to be
recognized and traced, though it may actually be intermittent in the
instance before us, and its colour has to be distinguished from any other
patches of red which there may happen to be in the field of view. So with
the

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other colours ; and the group of all together has to be united into a
somewhat artificial mental whole. What reason have we to suppose that the
dog goes through all this analysis and synthesis in a matter which cannot
possess the slightest interest for him ? So much however are we in the
habit of regarding what we call ‘objects’ as being in a way marked out by
nature, always and for all beings, that to raise a doubt whether the dog
really sees the rainbow would be taken by many persons as indicating a
disbelief in his actual optical powers. One might however almost as
reasonably expect him to see, say, the ‘ Progress of Democracy ’ in the
place where he lives, of which course of events the ultimate constituent
sensible elements are accessible to his observation precisely as they are
to ours.

If the reader feels any difficulty in accepting the above suggestion he
need only pause to consider what range of difference exists, as a matter of
present fact, between one person and another in respect of what they
recognize. The following simple example will serve our purpose. Every one
who has once had the appearance brought under his notice, is familiar with
the curious and regular curvilinear patterns which present themselves when
the wheels of a rapidly passing carriage are looked at a little sideways,
so that the centres of the two wheels are not quite in the same line of
vision^1. In certain respects these patterns have a remote analogy to the
rainbow, — e.g. in that they arise out of a certain fixity of instantaneous
relation to us of elements which are themselves in rapid motion; in that it
may be maintained that no two persons can be said to see the same object
strictly: and so on; — and they have exactly the same title, neither more
nor less, to be regarded as objective entities, viz. as ‘ things ’.
Inasmuch as they are of no importance to us, and have not, like the
rainbow, acquired a name, very few persons ever notice them. Once pointed
out, they readily force themselves upon the view; but though every day

^1. They arise from the fact that certain portions of the overlapping
spokes, at any given moment, lie longer in the same line of vision, and
consequently cause a more durable after image. The determination of the
exact pattern is of course a mere geometrical problem. The modern bicycle,
with its polished steel spokes arranged in two approximately parallel
circles on each wheel, shows the pattern much more vividly; so that in the
case of these machines we do not find the striking contrast between one
observer being unable not to see what ninety-nine others under similar
circumstances are unable to see.

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in London there must be tens of thousands of persons who have all the
requisite impressions made on the retina, experience shows that an
extremely small proportion of mankind have ever seen them.

The logical bearings of the above state of things are manifold, and will
have to be discussed in due place as they present themselves. The most
obvious of these bearings is that on the nature of the Categories, — if we
interpret these, with Mill, as being the most fundamental divisions and
classifications of all Narneable Things — for we cannot satisfactorily
establish the range of these unless we have realized the exceedingly
complex and artificial character of many of them. Similarly with the nature
of propositions; the relation of subject and predicate; the distinction
between existential propositions and those which involve a distinct copula;
nay also, — as I shall hope to show, — much of the difference between the
hypothetical and categorical forms of statement. We shall never treat these
satisfactorily unless we realize that Logic must take it for granted, as
one of its postulates, that an enormous amount of this object-manufacture
has been already got through and that the result lies ready to hand for
further use.

One obvious objection may be noticed here. It may be urged that, so far
from this process of analysis and synthesis of elements — by which, as we
have just pointed out, the various objects which collectively form the vast
complex of our logical world, have been put together, — being presupposed
by Logic, such processes are really the principal subject-matter of the
science. For what else, it may be urged in many cases, are affirmation and
denial but just this very process of analysis and synthesis ? There is some
truth in this objection. As will be shown more fully in the sequel, the act
of predication, in its twofold aspect of affirmation and denial, really is
a process by which we are not only enabled to add to our information about
objects, but is also the process by the continued performance of which
these same objects had originally been acquired, or rather produced. This
needs further exposition, and will receive it in due place, as it involves
a difficulty which presents itself under varying aspects at several
different points in the study of Inductive Logic. At present it is only
necessary to insist that extensive results of such a process must be
presupposed at every

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assigned time and place at which the thinker may be supposed to appeal to
his Logic, unless he proposes to set to work to discuss the rational
development of the human race from its first commencement: in other words
to make his Logic a chapter in evolutionary Psychology. We can no more
evade this necessity than we can conceive our reaching a last possible
subdivision of space. Whatever example of a proposition we select contains
a subject and a predicate, and one, if not both of these, will consist of
an object of some kind. This remains true however far back we may insist on
pushing our analysis.

To sum up, then ; before the logician can set to work he must have his
materials before him, and his materials, unlike those of the psychologist,
must always be terms, or the notions corresponding to these terms. These
presuppose a considerable amount of that analysis and synthesis which has
been indicated above. The psychologist may afford to start with simple
impressions, but the logician’s starting-point must always be a stage
further on. It must be the stage in which we stand in possession of ‘
objects ‘ distinctly recognized as such.

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--
Matt