Induction is an inference from many facts. Induction is verification.
Just as in a syllogism we show that a part is contained in the whole, so
in induction we show that a part is illustrated by the whole. It seems
that every single fact contains many truths, but induction establishes
their _universality_. A single brain contains all the truths of
phrenology, a single stone includes the phenomena of gravitation, the
temperance of a single individual exhibits the whole law of moderation,
but we learn the universality of these truths by induction.
Every legal statute, says Dr. Johnson, is founded on induction. 'Law is
the science in which the greatest powers of understanding are applied
to the greatest number of facts.' The _basis of all_ science is such an
extensive induction of particulars as leads to general definitions and
fundamental axioms, and furnishes the premises from which inferences may
be deduced.
Inductive observation is the great instrument of discovering important
truths. 'What are called the principles of human nature are learned from
individual instances. It is the only possible way of learning them. *
* When we reason from a general law or principle, we are in truth
reasoning from a number of instances represented by It.'*
* Rationale of Political Representation, p. 34.
A general election is an induction of the intelligence of the country
represented by the members of Parliament. The difference between
democracy and monarchy is in one sense an affair of logic. Where
electors are limited in franchise, and candidates restricted by property
qualification, the induction is partial, but where all can vote and many
can be chosen from, the premises are more capacious and the inference
sounder.
Dr. Whately says, that 'in Natural Philosophy a _single instance_ is
often accounted a _sufficient_ induction; e.g., having once ascertained
that an individual magnet will attract iron, we are authorised to
conclude that this property is universal.'
'The Edinburgh Reviewer of Whewell's "History of the Inductive
Sciences," observes that, "by the _accidental_ placing of a rhomb
of calcareous spar, upon a book or line, Bartholinus discovered the
property of the double refraction of light. By _accidentally_ combining
two rhombs in different positions, Huygens discovered the polarisation
of light. By _accidentally_ looking through a prism of the same
substance, and turning it round, Mains discovered the polarisation of
light by reflection; and by placing thin chrystalline films between two
similar prisms or rhombs, M. Arago discovered the phenomena of polarised
tints."
'To this Mr. Whewell, in his "Philosophy of the Inductive Sciences,"
makes the following reply:--"But Bartholinus could have seen no such
consequence in the accident, if he had not previously had a clear
conception of single refraction. A lady, in describing an optical
experiment which had been shown her, said of her teacher, 'he told me
to increase and diminish the angle of refraction: and, at last, I found
that he only meant me to move my head up and down.' At any rate, till
the lady had acquired a knowledge of the meaning which the technical
terms convey, she could not have made Bartholinus's discovery by means
of this accident. Suppose that Huygens made the experiment alluded to,
without design, what he really observed was that the images appeared
and disappeared alternately as he turned the rhomb round. His success
depended on his clearness of thought, which enabled him to perform
the intellectual analysis which would never have occurred to most men,
however often they had combined two rhombs in different positions. Malus
saw that in some positions the light reflected from the windows of
the Louvre became dim. Another person would have attributed this to
accident; he, however, considered the position of the prism, and the
window; repeated the experiment often; and by virtue of the eminently
distinct conceptions of space which he possessed, resolved the
phenomenon into its geometrical conditions."* "If it were true, that
the fall of an apple was the occasion of Newton's pursuing that train of
thought which led to the doctrine of universal gravitation, the habits
and constitution of Newton's intellect were the real source of this
great event in the progress of knowledge."** "In whatever manner facts
may be presented to the notice of a discoverer, they can never become
the materials of exact knowledge, except they find his mind already
provided with precise and suitable conceptions, by which they may be
analysed and connected."'***
* Whewell: Phil. Induct. Sciences, vol. 2. pp. 199-1.
** Ibid, vol. 2, p. 189.
*** See J. N. Bailey's Essays pp. 87-8-9.
These admissions seem to me to prove that whenever a casual fact proves
to us a new truth, it does so by its coincidence with previously known
facts, and that the novelty of the occasion attracts all credit to
itself, and we lose sight of the generalisation below--the fruitful
soil of experience on which the new fact, like a seed, falls. We only
recognise difference by comparison, and the comparison is an induction,
however slender.
Monsieur de Montmorine was recaptured and brought to the scaffold,
through the trifling circumstance of some chicken bones being found near
the door of his landlady--a woman too poor to indulge in such dainties.*
The discovery of de Montmorine was not, as at first sight appears, an
inference from a single fact, but from an adjacent induction. It was
a general truth, (known to the party who observed the bones) a truth
inducted from a number of facts that poor people could not afford to
luxuriate on chickens. It was, therefore, from this induction, inferred
that some one of superior fortune must be living in that particular
place.
* Chambers' Miscellany of Useful and Entertaining Tracts,
No. 61: the Story of Lavaiette, p. 27
The judicious care which the great fathers of science have exhibited in
making their inferences, incontestably establishes their conviction
of the danger of any other reasoning than that from inductions. Lord
Brougham informs us, that what Newton's Principia is to science, Locke's
essay to metaphysics, Demosthenes in oratory, and Homer in poetry,
Cuvier's researches to our fossil osteology. But Cuvier never attempted
to draw any inferences until he had examined the _whole_ osteology of
the living species.
Lord Brougham remarks, that 'from examining a _single_ fragment of bone
we infer that, in the wilds where we found it, there lived and ranged,
some thousands of years ago, an animal of a peculiar kind.' This is a
case in which the inference spoken of is arrived at in a way different
from that apparently stated. We recognise in the 'fragment of bone'
a link in a chain of facts constituting the basis of a well-known
induction, which comparative anatomy has many times verified. It
is important to distinguish well the grounds from which accurate
inferences, such as these in the cases before us, have really been
adduced, in order to ascertain the grounds from which we should reason
generally. It will be found that solid reasoning can only proceed from
general rules--i.e., inductions from facts. It will be found that the
prime source of fallacy lies in reasoning from isolated facts. It is
not to be denied that such reasoning is sometimes right, but it is to
be remembered that it is right by accident, not by design. There is no
science or certainty in it. It is hazard, not logic.
This habit however, is very common. Mr. Mill says, that 'Not only _may_
we reason from particulars to particulars, without passing through
generals, but we perpetually do so reason. All our earliest inferences
are of this nature. From the first dawn of intelligence we draw
inferences, but years elapse before we learn the use of general
language. The child, who, having burnt his fingers, avoids to thrust
them again into the fire, has reasoned or inferred, though he has never
thought of the general maxim--fire burns. He knows from memory that he
has been burnt, and on this evidence believes, when he sees a candle,
that if he puts his fingers into the flame of it, he will be burnt
again. He believes this in every case which happens to arise; but
without looking, in each instance, beyond the present case. He is not
generalising; he is inferring a particular from particulars. In the same
way, also, brutes reason. There is little or no ground, for attributing
to any of the lower animals the use of conventional signs, without
which general propositions are impossible. But those animals profit by
experience, and avoid what they have found to cause them pain, in the
same manner, though not always with the same skill, as a human creature.
Not only the burnt child, but the burnt dog, dreads the fire.
'I believe that, in point of fact, when drawing inferences from our
personal experience, and not from maxims handed down to us by books
or tradition, we much oftener conclude from particulars to particulars
directly, than through the intermediate agency of any general
proposition. We are constantly reasoning from ourselves to other people,
or from one person to another, without giving ourselves the trouble to
erect our observations into general maxims of human or external nature.
When we conclude that some person will, on some given occasion, feel or
act so and so, we sometimes judge from an enlarged consideration of the
manner in which men in general, or men of some particular character,
are accustomed to feel and act; but much oftener from having known the
feelings and conduct of the same man in some previous instance, or from
considering how we should feel or act ourselves. It is not only the
village matron who, when called to a consultation upon the case of a
neighbour's child, pronounces on the evil and its remedy simply on the
recollection and authority of what she accounts the similar case of
her Lucy. We all, where we have no definite maxims to steer by, guide
ourselves in the same way; and if we have an extensive experience, and
retain its impressions strongly, we may acquire, in this manner, a
very considerable power of accurate judgment, which we may be utterly
incapable of justifying or of communicating to others. Among the higher
order of practical intellects, there have been many of whom it was
remarked how admirably they suited their means to their ends, without
being able to give any sufficient reasons for what they did and
applied, or seemed to apply, recondite principles which they were wholly
unable to state. This is a natural consequence of having a mind stored
with appropriate particulars, and having been long accustomed to reason
at once from these to fresh particulars, without practising the habit of
stating to oneself or to others the corresponding general propositions.
An old warrior, on a rapid glance at the outlines of the ground, is able
at once to give the necessary orders for a skilful arrangement of his
troops; though if he has received little theoretical instruction, and
has seldom been called upon to answer to other people for his conduct,
he may never have had in his mind a single general theorem respecting
the relation between ground and array. But his experience of
encampments, under circumstances more or less similar, has left a number
of vivid, unexpressed, ungeneralised analogies in his mind, the most
appropriate of which, instantly suggesting itself, determines him to a
judicious arrangement.
'The skill of an uneducated person in the use of weapons, or of tools,
is of a precisely similar nature. The savage who executes unerringly the
exact throw which brings down his game, or his enemy, in the manner
most suited to his purpose, under the operation of all the conditions
necessarily involved, the weight and form of the weapon, the direction
and distance of the object, the action of the wind, &c., owes this
power to a long series of previous experiments, the results of which he
certainly never framed into any verbal theorems or rules. It is the
same in all extraordinary manual dexterity. Not long ago a Scotch
manufacturer procured from England, at a high rate of wages, a working
dyer, famous for producing very fine colours, with a view of teaching
to his other workmen the same skill. The workman came; but his mode of
proportioning the ingredients, in which lay the secret of the effects he
produced, was by taking them up in handfuls while the common method was
to weigh them. The manufacturer sought to make him turn his handling
system into an equivalent weighing system, that the general principle of
his peculiar mode of proceeding might be ascertained. This, however,
the man found himself quite unable to do, and therefore could impart
his skill to nobody. He had, from the individual cases of his own
experience, established a connection in his mind between fine effects
of colour, and tactual perceptions in handling his dyeing materials;
and from these perceptions he could, in any particular cases, infer the
means to be employed, and the effect which would be produced, but could
not put others in possession of the grounds on which he proceeded, from
having never generalised them in his own mind, or expressed them in
language.
'Almost every one knows Lord Mansfield's advice to a man of practical
good sense, who, being appointed governor of a colony, had to preside
in its court of justice, without previous judicial practice or legal
education. The advice was to give his decision boldly, for it would
probably be right; but never to venture on assigning reasons, for they
would almost infallibly be wrong. In cases like this, which are of no
uncommon occurrence, it would be absurd to suppose that the bad reason
was the source of the good decision. Lord Mansfield knew that if any
reason were assigned it would be necessarily an afterthought, the judge
being _in fact_ guided by impressions from past experience, without the
circuitous process of framing general principles from them, and that if
he attempted to frame any such he would assuredly fail. Lord Mansfield,
however, would not have doubted that a man of equal experience, who
had also a mind stored with general propositions derived by legitimate
induction from that experience, would have been greatly preferable as
a judge, to one, however sagacious, who could not be trusted with the
explanation and justification of his own judgments. The cases of able
men performing wonderful things they know not how, are examples of the
less civilised and most spontaneous form of the operations of superior
minds It is a _defect in them_, and _often a source of errors_, not to
have generalised as they went on; but generalisation is a help, the most
important indeed of all helps, yet not an essential.'*
* Mill's Logic, pp. 251-5.
In illustration of generalising from single instances, Miss Martineau
gives this example:--'A raw Chinese traveller in England was landed by
a Thames waterman who had a wooden leg. The stranger saw that the wooden
leg was used to stand in the water with, while the other was high and
dry. The apparent economy of the fact struck the Chinese; he saw in it
strong evidence of design, and wrote home that in England one-legged men
are kept for watermen, to the saving of all injury to health, shoe, and
stocking, from standing in the river.'*
Reasoning on insufficient data--
Falls like an inverted cone,
Wanting its proper base to stand upon.
Samuel Bailey has furnished, in one passage, both a clear illustration
of the process, and the validity of an induction:--'Whoever had
witnessed the acts of a landlord to his tenants, of a schoolmaster to
his pupils, of artizans towards their apprentices, of husbands towards
their wives, on points where the power of the superior could not be
contested, and where his personal gratification was incompatible with
just conduct to the subordinate, would necessarily have formed in his
own mind a species of general rule; and from this rule he might safely
draw an inference as to what would be the conduct of a despot, seated on
a throne, in the possession of unchecked authority; assisted too, as the
inquirer would be, by that _indispensable and inestimable guide to the
knowledge of mankind, an appeal to his own feelings_, in a variety of
_analogous_ instances.
'We conclude, that a ruler with uncontrolled power will act the tyrant,
not merely from the fact that Caligula, or Nero, or Bonaparte did,
but from a thousand facts attesting that men, in, every situation, use
uncontrolled power in this way--just as we infer that all bodies tend to
the centre of the earth, _not merely from the circumstance of an apple
dropping from a tree, but from seeing the tendency in stones, water,
animals, and all things within our observation_. The use of uncontrolled
power, for the gratification of the possessor, without an equitable
respect to others, is no more peculiar to monarchs, than a tendency
to the earth is peculiar to apples. It may be useful to know that
_monarchs_ act in this way, as it may be useful to know that apples drop
to the ground; but it is much more useful to know that _men_ act in
this manner. _An inference is safer when gathered from the widest
induction.'_
* How to Observe, p. 6.
** Rationale of Political Representation. Introduction, pp.
85-6. The last sentence of this extract is abridged--but, as
the reader will find upon reference, the sense of the author
is faithfully rendered.
It may be useful to observe that, though a few instances are insufficient
to establish a theory, one may be sufficient to overturn a theory,
fancifully or hypothetically supported, Gibbon overturns the entertaining
theory of Rudbeck, an antiquarian of Upsal, of profound learning and easy
faith, who, by the dim light of legends and traditions, of conjectures
and etymologies, sought to establish the antiquity of Sweden over half
the earth. Gibbon annihilated this well laboured system of German
antiquities, by a single fact too well attested to admit of any doubt,
and of too decisive a nature to leave room for any reply--the fact that
the Germans, of the age of Tacitus, were unacquainted with the use of
letters. A circumstance fatal to their literary claims, urged by Olaus
Rudbeck.
In the chapter on 'Facts' I have cautioned the reader against
unquestioned data. This seems the place to remark that the unsuspected
sources of error and unfriendliness have their rise in the criminal
implicitness with which we listen to reports, and infer from rumours as
from facts. These are the very little handles which move men and women
to strange performances.'* All the plots of dramas and romances are
founded on misunderstandings, which a little sagacity of action (such as
a wise resolution not to be imposed upon would lead to) would commonly
suffice to arrest the error at its birth. With regard to character we
constantly infer from data, partial, limited, and doubtful. If most
quarrelers were called into a court of Inquiry to confess the real
grounds from which they have arrived at certain conclusions with regard
to their neighbours, and often with regard to their friends, they would
be at once overwhelmed with a conviction of the weakness of which they
have been guilty. Upon analysing the miserable sources of opinions
of which scandal and calumny are born, I have found it impossible
to restrain astonishment at the imbecility of logical power men will
sometimes be content to exhibit, where meanness prevails, malice
incites, and passion governs. Well might Bacon exclaim--'Doth any man
doubt, that if there were taken out of men's minds, vain opinions,
flattering hopes, false valuations, imaginations, and the like, but it
would leave the minds of a number of men poor shrunken things?'** The
wise rule is, never judge from appearances when facts can be had--never
receive a report without challenging its foundation, nor adopt it
without permission to give the authority.
* Cricket on the Hearth.
** Essay on Truth.
In all cases, in which you must judge from appearances and reason
from conjectures, adopt the _fairest_ interpretation possible. On this
principle, credit will sometimes be given where none is due--but in nine
cases out of ten, justice will be done, for I am satisfied that there is
more worth among men than wisdom, and that we do well much oftener than
we reason well. We seldom need judge charitably, did we always endeavour
to judge justly. But we make a virtue of our own errors, and we often
affect to _condescend_ to pronounce an opinion, which it would be
criminal to withhold. If ever I go to the Herald's, office, the motto I
will have emblazoned shall be this--Justice is sufficient. Could we only
get justice in the world, we could afford to excuse it all its 'charity'
of judgment, and its benevolence even of act.
Where should a man's reputation be safe from suspicion if not in the
hands of his friend? It ought to be a principle of action with all
men, never to judge a friend except out of his own mouth. 'There was
a generous friend of mine once, who never would have judged me or any
other man unheard.'* With the sublime intensity of one who felt the
infinite value of private justice, has Schiller delineated this spirit
in the interview between Octavio and his son Max Piccolomini. After
a violent and visible struggle with his feelings--wrought upon by his
father's endeavours to sow suspicions in his mind, and detach him from
the service of his friend, Wallenstein--Max exclaims:--
* Edward to Mr. Peerybing.
I will procure me light a shorter way. Farewell.
Octavio. Where now?
Max. (To the Duke.)
If thou hast believed that I shall act
A part in this thy play----
Thou hast miscalculated on me grievously.
My way must be straight on.
True with the tongue,
False with the heart--I may not, cannot be:
Nor can I suffer that a man should trust me--
As his friend trust me--and then lull my conscience
With such low pleas as these:--"I ask him not--
He did it all at his own hazard--and
My mouth has never lied to him."--No, no
What a friend takes me for, that I must be.
--I'll to the Duke; ere yet this day is ended
Will I demand of him that he do save
His good name from the world, and with one stride
Break through and rend this fine-spun web of yours.
He can, he will!--I still am his believer.
Yet I'll not pledge myself, but that those letters
May furnish you, perchance, with proofs against him.
How far may not this Tertsky have proceeded--
What may not he himself too have permitted
Himself to do, to snare the enemy,
The laws of war excusing? Nothing, save
His own mouth shall convict him--nothing less!
And face to face will I go question him.
Ay--this state-policy? O how I curse it!
You will some time, with your state-policy,
Compel him to the measure; it may happen
Because ye are _determined_ that he is guilty,
Guilty ye'll make him. All retreat cut off,
You close up every outlet, hem him in
Narrower and narrower, till at length ye force him--
Yes, ye,--ye force him in his desperation,
To set fire to his prison. Father! father!
That never can end well--it cannot--will not!
Deem of it what thou wilt; but pardon me,
That I must bear me on in my own way.
All must remain pure betwixt him and me;
And, ere the day-light dawns, it must be known
Which I must lose--my father, or my friend.*
* Shiller's Piccolomini, act 3, scene 9.
Had Othello been thus honourable to Desdemona, he would never have
murdered her. Incalculable is the evil we bring on ourselves and
society, by supposing and surmising facts we ought resolutely to
question. The motto of the garter--
Evil be to him who evil thinks,
ought to be,
Evil is to him who evil thinks.
Every man will be his own Lawyer and his own Doctor, and such is the
perversity of human nature, he will also be his own _Iago_, and feed
himself with suspicions. Nearly all tragedies hinge on this error.
To avoid being the cause of misunderstanding to others, it is a good
rule never to speak critically of others, except in their presence, or
in print. When I am obliged to do this in conversation, with persons of
unknown or doubtful exactitude, I take care to keep much below the truth
in matters of censure, as anything of that kind may gain ten or twenty
per cent, in carriage. When with men of just habits of interpretation,
I pay them the highest compliment of friendship, and speak to them of
others, without reserve.
Notorious are the contumelies put upon the cases of grievance presented
from the people in the House of Commons. Nor is it altogether causeless.
So prone are the ignorant to mistake their prejudices for facts, and
ascribe to others as crimes what exists only in their own surmises, that
most popular cases may be stripped of half their pretensions without
injuring their truth. Exaggeration is the vice of ignorance. Half the
speeches addressed to 'King Mob' are hyperbolic. The sentiments of
public meetings minister too often to the prevalent inflation. The
people will be powerful when they learn to be exact--and not till then.
The only mode of correcting this evil is to instil into the people the
wise rule of Burlamiqui. To reason, (that is, inductively) says this
writer, is to calculate, and as it were draw up an account, after
balancing all arguments, in order to see on which side the advantage
lies. Burlamiqui had law chiefly in view in his remark, but the rule is
of immense application. A logician is a secretary or banker's clerk, who
keeps an account between truth and error. When a lady once consulted Dr.
Johnson on the degree of turpitude to be attached to her son's robbing
an orchard--'Madam,' said Johnson, 'it all depends upon the weight of
the boy. I remember my schoolfellow, Davy Garrick, who was always a
little fellow, robbing a dozen orchards with impunity, but the very
first time I climbed up an apple tree, for I was always a heavy boy, the
bough broke with me, and it was called a judgment. I suppose that is
why Justice is represented with a pair of scales.' This may not be the
precise reason why Justice has a pair of scales, but the point goes to
the root of the matter. Without weighing there can be neither justice
nor fair induction.
In illustration of these views Mr. Mill has some able remarks:--'In
proportion to any person's deficiency of knowledge and mental
cultivation, is generally his inability to discriminate between his
inferences and the perceptions on which they were grounded.
Many a marvellous tale many a scandalous anecdote, owes its origin to
this incapacity. The narrater relates, not what he saw or heard, but
the impression which he derived from what he saw or heard, and of which
perhaps the greater part consisted of inference, though the whole
is related not as inference but as matter-of-fact. The difficulty
of inducing witnesses to restrain, within any moderate limits,
the intermixture of their inferences with the narrative of their
perceptions, is well known to experienced cross-examiners; and still
more is this the case when ignorant persons attempt to describe any
natural phenomenon. "The simplest narrative," says Dugald Stewart, "of
the most illiterate observer involves more or less of hypothesis nay,
in general, it will be found that, in proportion to his ignorance,
the greater is the number of conjectural principle involved in his
statements. A village apothecary (and, if possible, in a still greater
degree, an experienced nurse) is seldom able to describe; the plainest
case, without employing a phraseology of which every word is a theory;
whereas a simple and genuine specification of the phenomena which mark a
particular disease--a specification unsophisticated by fancy, or by
preconceived opinions, may be regarded as unequivocal evidence of a mind
trained by long and successful study to the most difficult of all arts,
that of the faithful _interpretation_ of nature."'*
* Logic, pp. 408-9, vol. 2.
It is in judgments formed, in reprehensible indifference to the actual
facts of the case, that party rancour and the proverbial injustice of
popular political opinion take their rise. A useful caution on this
head is pronounced by Lord Brougham in his sketch of the life of Lord
Wellesley:--'How often do we see,' observes his lordship, 'vehement: and
unceasing; attacks made upon a minister or a statesman, perhaps not in
the public service, for something which he does not choose to defend or
explain, resting his claims to the confidence of his countrymen upon
his past exertions and his known character. Yet these assaults are
unremittingly made upon him, and the people believe that so much noise
could not be stirred up without something to authorise it. Sometimes the
objects of the calumny are silent from disdain; sometimes from knowing
that the base propagators of it will only return to their slander the
more eagerly alter their conviction of falsehood; but sometimes, also,
the silencer may be owing to official reserve, of which we see a most
remarkable instance in the ease of Lord Wellesly.'
Not only are enemies of the people afforded a justification for their
opposition by wrongful judgment pronounced upon them, but the friends
of the people often pass over to the other side through the same cause.
When a leader of the people first comes in personal contact with the
opposite party, and becomes acquainted with merits of feeling and
judgment which he had as it were pledged himself to deny, and indeed
achieved himself a position by disbelieving in, he becomes ashamed of
the injustice exacted from him by his inexorable adherents, and forsakes
his party when he should only forsake its errors. The case of Barnave,
in the first French Revolution, is a memorable instance of this. On
lesser theatres I have seen many instances of this kind of conversion;
Such changes have always been ascribed to venality, yet they are men
of generous instincts who are thus overcome--but they want logical
strength, and cannot correct themselves without falling.
It is a wise rule in conversation, never to guess at meanings. When, an
observation is made, capable of affording two inferences, at once put
the question which shall elicit the meaning intended. Conversation is
held to no purpose unless explicitness comes out of it. Innumerable are
the errors that arise through letting remarks pass, of which we
only _suppose_ we know the purport. This is a fruitful source of
misunderstanding. When in Scotland I was much instructed by the
intellectual characteristics of the people. The Scotch are essentially a
reflective people. The English conceive doubts, but the Scotch put them
into queries. Before I had been in the country many hours I was struck
by the inductive habits of the people. A very old and illiterate woman,
to whom I put an indefinite question, eyed me deliberately from head to
foot before she gave me an answer. Not in rudeness did she gaze, so much
as in inquiry as to what could be my object. I spent more than a week
in inquiring at places, where apartments were to be let, by which I
acquired profitable acquaintance with the people. Upon asking the
terms of apartments, I was met, in all cases, by several preliminary
questions, as for whom were they? what number of persons? what station,
habits, and probable stay? Then I received the precise answer required.
It did not seem to me that they were answering one question by asking
another, as is sometimes said of the Scotch--but by a happy and wise
presence of mind they asked, as all should do, at many questions as were
required to complete the data of the specific answer they were called
upon to give.
A wise practice is followed in courts of law. No judge pronounces an
opinion on a hypothetical case. What he would do? or what would be the
judgment of the law, suppose a certain case should arise?--are questions
he never condescends to answer. 'Bring the plaintiff into court, let the
evidence be taken, and then we will decide. We sit here to judge actual,
not suppositious cases.' Such would be the reply. People out of court
might profit by the example.
I remember one striking instance of the pernicious effects of surmise.
Some years ago I took part in a Fraternal Demonstration at Highbury
Barn. The assembly was numerous, and composed of persons of all nations
and all parties. The celebration was avowedly one of fraternity. The
tone of the meeting reflected its object. Pacific words were on every
tongue, and harmony reigned up till eleven o'clock. At that hour
Monsieur Chillman asked me if some steps could not be taken to annualize
the meeting, and he requested me to prepare and propose a resolution to
that effect. Monsieur Chillman, thinking the resolution ought to come
from an Englishman, strongly urged me to move it. I, thinking it too
important to emanate from a young man, looked about for a person of
experience and known discretion to introduce it. After several had
declined, Mr. Hetherington undertook it. The English politicians were
composed of two parties, the friends of Mr. O'Connor, and the members of
the National Hall. At that time they were pleased to be the antipodes of
each other. No sooner had Mr. Hetherington spoken, he being the friend
of Mr. Lovett, than his motion was supposed to come from Mr. Lovett's
party, though they were utterly ignorant of its origination. Clamour's
hundred tongues were loosened. Slumbering differences were awakened.
Suspicion spread like an infection. Fraternity perished of the
contagion. Twenty amendments were proposed, and it was not till
midnight, and then in a storm indescribably contradictory of the
meeting's whole purport, that a common understanding was come to.
Had the least inquiry been made by the objecting party, previously
to dissenting, they would have found that the suspicious proposition
originated with one of themselves. But assuming premises, they inferred
from conjecture instead of fact, and raised disastrous doubts as to the
ability of that assembly for domestic or international fraternisation.
The use and abuse of authority Is a subject worthy of the young
logician's serious attention. Many great writers like Bacon, through
policy--Burke through position, or Shakspere through versatility of
genius, have written on both sides of important questions. Such men,
taken piece-meal, may be quoted by the most opposite parties in favour
of the most opposite opinions. Unless there is time to make a broad
induction from their writings, showing, by weighty, quantitive evidence,
the side to which they leaned, better not quote them as _authorities_
at all, but give what expresses your own views on your own
responsibility--indeed, in _all_ cases, the quoter ought to stand
prepared, if possible, to justify all he cites from another in argument.
'There is perhaps something weak and servile in our wishing to rely
on, or draw assistance from, ancient opinions. Reason ought not, like
vanity, to adorn herself with old parchments, and the display of a
genealogical tree; more dignified in her proceedings, she ought to
derive everything from herself; she should disregard past times, and be,
if I may use the phrase, the contemporary of all ages.'* Quote others as
Grotius did: not as judges from whose decision there is no appeal, but
as witnesses whose conspiring testimony confirms the view taken.
* Necker.
Analogy has frequently been confounded with induction. Analogy signifies
reasoning from resemblances subsisting between phenomena--induction,
reasoning from the sameness of phenomena.
The phenomena affording an induction of a law of nature must be obvious,
uniform, and universal.
The rules to be observed in deducing general principles are, that the
case be true and the facts universal.
On this subject, as exhibiting the clearest results arrived at, I
transcribe a passage from Mill: 'There is no word which is used more
loosely, or in a greater variety of senses, than analogy. It sometimes
stands for arguments which may be examples of the most rigid induction.
Archbishop Whately, for instance, following Ferguson and other writers,
defines analogy conformably to its primitive acceptation, that which was
given to it by mathematicians, resemblance of relations. In this sense,
when a country which has sent out colonies is termed the mother country,
the expression is analogical, signifying that the colonies of a country
stand in the same _relation_ to her in which children stand to their
parents. And if any inference be drawn from this resemblance of
relations, as, for instance, that the same obedience or affection is
due from colonies to the mother country which is due from children to a
parent, this is called reasoning by analogy. Or if it be argued that
a nation is most beneficially governed by an assembly elected by the
people, from the admitted fact that other associations for a common
purpose, such as joint stock companies, are best managed by a committee
chosen by the parties interested; this, too, is an argument from analogy
in the preceding sense, because its foundation is, not that a nation is
like a joint stock company, or Parliament like a board of directors, but
that Parliament stands in the same _relation_ to the nation in which a
board of directors stands to a joint stock company. Now, in an argument
of this nature, there is no inherent inferiority of conclusiveness like
other arguments from resemblance, it may amount to nothing, or it may
be a perfect and conclusive induction. The circumstance in which the
two cases resemble, may be capable of: being shown to be the _matereal_
circumstance; to be that on which all the consequences, necessary to be
taken into account in the particular discussion, depend. In the case
in question, the resemblance is one of relation; the _fundamentum
relationis_ being the management, by a few persons, of affairs in which
a much greater number are interested along with them. Now, some may
contend that this circumstance which is common to the two cases, and
the various consequences which follow from it, have the chief share in
determining all those effects which make up what we term good or bad
administration. If they can establish this, their argument has the force
of a rigid induction: if they cannot, they are said to have failed
in proving the analogy between the two cases, a mode of speech which
implies that when the analogy can be proved, the argument founded upon
it cannot be resisted.'*
* Logic, pp. 97-8, vol. 2.
'Many of the most splendid and important discoveries in this science
were the result of analogical reasonings. It was from this source that
Dr. Priestley proved the compound nature of atmospheric air; and it is
related that it was in consequence of hints which he had given, when
on a visit to Paris, to Lavoisier, founded entirely upon analogical
conjectures, that the latter philosopher was induced to commence
experiments, with the view of proving the compound nature of water, and
of reducing it to its constituent elements. Indeed the whole history of
this very important and useful department of human knowledge exhibits
very striking and incontestable proofs how much of the art owed its
existence to mere hints and conjectures, founded, in many cases, upon
very slight resemblances or analogies.*. The chief province of analogy
is confined to that of suggestion. Analogies are the great hinters of
experiments. They illustrate an argument, but do not establish it.
They are probabilities, not proofs. Hence Lord Brougham in one place
exclaims:--'I have a dread, at least a suspicion, of all analogies, and
never more than when on the slippery heights of an obscure subject;
when we are, as it were, _inter apices_ of a metaphysical argument, and
feeling, perhaps groping, our way in the dark, or among the clouds.
I then regard analogy as a dangerous light, a treacherous _ignii
fatuus_.'**
A striking instance of the fallacy of analogy is afforded in the
experiments of Professor Matteuoci, which seem to prove that though the
analogies between electricity and nervous substance are nearly perfect,
yet they are two distinct agencies.***
* Blakey's Logic, pp. 97-7.
** Pal. Illus. vol. 2.
*** See Zoist No. 20, p. 363.