CHAPTER VI

STUDY AND RESEARCH IN MATHEMATICS

=601.= The first thing to be attended to in reading any algebraic

treatise is the gaining a perfect understanding of the different

processes there exhibited, and of their connection with one

another. This cannot be attained by the mere reading of the book,

however great the attention which may be given. It is impossible

in a mathematical work to fill up every process in the manner in

which it must be filled up in the mind of the student before he

can be said to have completely mastered it. Many results must be

given of which the details are suppressed, such are the

additions, multiplications, extractions of square roots, etc.,

with which the investigations abound. These must not be taken on

trust by the student, but must be worked out by his own pen,

which must never be out of his own hand while engaged in any

mathematical process.--DE MORGAN, A.

_Study and Difficulties of Mathematics

(Chicago, 1902), chap. 12._

=602.= The student should not lose any opportunity of exercising

himself in numerical calculation and particularly in the use of

logarithmic tables. His power of applying mathematics to

questions of practical utility is in direct proportion to the

facility which he possesses in computation.--DE MORGAN, A.

_Study and Difficulties of Mathematics

(Chicago, 1902), chap. 12._

=603.= The examples which a beginner should choose for practice

should be simple and should not contain very large numbers. The

powers of the mind cannot be directed to two things at once; if

the complexity of the numbers used requires all the student’s

attention, he cannot observe the principle of the rule which he

is following.--DE MORGAN, A.

_Study and Difficulties of Mathematics

(Chicago, 1902), chap. 3._

=604.= Euclid and Archimedes are allowed to be knowing, and to

have demonstrated what they say: and yet whosoever shall read

over their writings without perceiving the connection of their

proofs, and seeing what they show, though he may understand all

their words, yet he is not the more knowing. He may believe,

indeed, but does not know what they say, and so is not advanced

one jot in mathematical knowledge by all his reading of those

approved mathematicians.--LOCKE, JOHN.

_Conduct of the Understanding, sect.

24._

=605.= The student should read his author with the most sustained

attention, in order to discover the meaning of every sentence. If

the book is well written, it will endure and repay his close

attention: the text ought to be fairly intelligible, even without

illustrative examples. Often, far too often, a reader hurries

over the text without any sincere and vigorous effort to

understand it; and rushes to some example to clear up what ought

not to have been obscure, if it had been adequately considered.

The habit of scrupulously investigating the text seems to me

important on several grounds. The close scrutiny of language is a

very valuable exercise both for studious and practical life. In

the higher departments of mathematics the habit is indispensable:

in the long investigations which occur there it would be

impossible to interpose illustrative examples at every stage, the

student must therefore encounter and master, sentence by

sentence, an extensive and complicated argument.--TODHUNTER, ISAAC.

_Private Study of Mathematics; Conflict

of Studies and other Essays (London,

1873), p. 67._

=606.= It must happen that in some cases the author is not

understood, or is very imperfectly understood; and the question is

what is to be done. After giving a reasonable amount of attention

to the passage, let the student pass on, reserving the obscurity

for future efforts.... The natural tendency of solitary students,

I believe, is not to hurry away prematurely from a hard passage,

but to hang far too long over it; the just pride that does not

like to acknowledge defeat, and the strong will that cannot endure

to be thwarted, both urge to a continuance of effort even when

success seems hopeless. It is only by experience we gain the

conviction that when the mind is thoroughly fatigued it has

neither the power to continue with advantage its course in an

assigned direction, nor elasticity to strike out a new path; but

that, on the other hand, after being withdrawn for a time from the

pursuit, it may return and gain the desired end.--TODHUNTER, ISAAC.

_Private Study of Mathematics; Conflict

of Studies and other Essays (London,

1873), p. 68._

=607.= Every mathematical book that is worth reading must be read

“backwards and forwards,” if I may use the expression. I would

modify Lagrange’s advice a little and say, “Go on, but often

return to strengthen your faith.” When you come on a hard or

dreary passage, pass it over; and come back to it after you have

seen its importance or found the need for it further on.

--CHRYSTAL, GEORGE.

_Algebra, Part 2 (Edinburgh, 1889),

Preface, p. 8._

=608.= The large collection of problems which our modern

Cambridge books supply will be found to be almost an exclusive

peculiarity of these books; such collections scarcely exist in

foreign treatises on mathematics, nor even in English treatises

of an earlier date. This fact shows, I think, that a knowledge of

mathematics may be gained without the perpetual working of

examples.... Do not trouble yourselves with the examples, make it

your main business, I might almost say your exclusive business,

to understand the text of your author.--TODHUNTER, ISAAC.

_Private Study of Mathematics; Conflict

of Studies and other Essays (London,

1873), p. 74._

=609.= In my opinion the English excel in the art of writing

text-books for mathematical teaching; as regards the clear

exposition of theories and the abundance of excellent examples,

carefully selected, very few books exist in other countries which

can compete with those of Salmon and many other distinguished

English authors that could be named.--CREMONA, L.

_Projective Geometry [Leudesdorf]

(Oxford, 1885), Preface._

=610.= The solution of fallacies, which give rise to absurdities,

should be to him who is not a first beginner in mathematics an

excellent means of testing for a proper intelligible insight into

mathematical truth, of sharpening the wit, and of confining the

judgment and reason within strictly orderly limits.--VIOLA, J.

_Mathematische Sophismen (Wien, 1864),

Vorwort._

=611.= Success in the solution of a problem generally depends in

a great measure on the selection of the most appropriate method

of approaching it; many properties of conic sections (for

instance) being demonstrable by a few steps of pure geometry

which would involve the most laborious operations with trilinear

co-ordinates, while other properties are almost self-evident

under the method of trilinear co-ordinates, which it would

perhaps be actually impossible to prove by the old geometry.

--WHITWORTH, W. A.

_Modern Analytic Geometry (Cambridge,

1866), p. 154._

=612.= The deep study of nature is the most fruitful source of

mathematical discoveries. By offering to research a definite end,

this study has the advantage of excluding vague questions and

useless calculations; besides it is a sure means of forming

analysis itself and of discovering the elements which it most

concerns us to know, and which natural science ought always to

conserve.--- FOURIER, J.

_Théorie Analytique de la Chaleur,

Discours Préliminaire._

=613.= It is certainly true that all physical phenomena are

subject to strictly mathematical conditions, and mathematical

processes are unassailable in themselves. The trouble arises from

the data employed. Most phenomena are so highly complex that one

can never be quite sure that he is dealing with all the factors

until the experiment proves it. So that experiment is rather the

criterion of mathematical conclusions and must lead the way.

--DOLBEAR, A. E.

_Matter, Ether, Motion (Boston, 1894),

p. 89._

=614.= Students should learn to study at an early stage the great

works of the great masters instead of making their minds sterile

through the everlasting exercises of college, which are of no use

whatever, except to produce a new Arcadia where indolence is

veiled under the form of useless activity.... Hard study on the

great models has ever brought out the strong; and of such must be

our new scientific generation if it is to be worthy of the era to

which it is born and of the struggles to which it is destined.

--BELTRAMI.

_Giornale di matematiche, Vol. 11, p.

153. [Young, J. W.]_

=615.= The history of mathematics may be instructive as well as

agreeable; it may not only remind us of what we have, but may

also teach us to increase our store. Says De Morgan, “The early

history of the mind of men with regards to mathematics leads us

to point out our own errors; and in this respect it is well to

pay attention to the history of mathematics.” It warns us against

hasty conclusions; it points out the importance of a good

notation upon the progress of the science; it discourages

excessive specialization on the part of the investigator, by

showing how apparently distinct branches have been found to

possess unexpected connecting links; it saves the student from

wasting time and energy upon problems which were, perhaps, solved

long since; it discourages him from attacking an unsolved problem

by the same method which has led other mathematicians to failure;

it teaches that fortifications can be taken by other ways than by

direct attack, that when repulsed from a direct assault it is

well to reconnoitre and occupy the surrounding ground and to

discover the secret paths by which the apparently unconquerable

position can be taken.--CAJORI, F.

_History of Mathematics (New York,

1897), pp. 1-2._

=616.= The history of mathematics is important also as a valuable

contribution to the history of civilization. Human progress is

closely identified with scientific thought. Mathematical and

physical researches are a reliable record of intellectual

progress.--CAJORI, F.

_History of Mathematics (New York,

1897), p. 4._

=617.= It would be rash to say that nothing remains for discovery

or improvement even in elementary mathematics, but it may be

safely asserted that the ground has been so long and so

thoroughly explored as to hold out little hope of profitable

return for a casual adventurer.--TODHUNTER, ISAAC.

_Private Study of Mathematics; Conflict

of Studies and other Essays (London,

1873), p. 73._

=618.= We do not live in a time when knowledge can be extended

along a pathway smooth and free from obstacles, as at the time of

the discovery of the infinitesimal calculus, and in a measure

also when in the development of projective geometry obstacles

were suddenly removed which, having hemmed progress for a long

time, permitted a stream of investigators to pour in upon virgin

soil. There is no longer any browsing along the beaten paths; and

into the primeval forest only those may venture who are equipped

with the sharpest tools.--BURKHARDT, H.

_Mathematisches und wissenschaftliches

Denken; Jahresbericht der Deutschen

Mathematiker Vereinigung, Bd. 11, p.

55._

=619.= Though we must not without further consideration condemn a

body of reasoning merely because it is easy, nevertheless we must

not allow ourselves to be lured on merely by easiness; and we

should take care that every problem which we choose for attack,

whether it be easy or difficult, shall have a useful purpose,

that it shall contribute in some measure to the up-building of

the great edifice.--SEGRE, CORRADI.

_Some Recent Tendencies in Geometric

Investigation; Rivista di Matematica

(1891), p. 63. Bulletin American

Mathematical Society, 1904, p. 465.

[Young, J. W.]._

=620.= No mathematician now-a-days sets any store on the

discovery of isolated theorems, except as affording hints of an

unsuspected new sphere of thought, like meteorites detached from

some undiscovered planetary orb of speculation.--SYLVESTER, J. J.

_Notes to the Exeter Association

Address; Collected Mathematical Papers

(Cambridge, 1908), Vol. 2, p. 715._

=621.= Isolated, so-called “pretty theorems” have even less value

in the eyes of a modern mathematician than the discovery of a new

“pretty flower” has to the scientific botanist, though the layman

finds in these the chief charm of the respective sciences.

--HANKEL, HERMANN.

_Die Entwickelung der Mathematik in den

letzten Jahrhunderten (Tübingen, 1884),

p. 15._

=622.= It is, so to speak, a scientific tact, which must guide

mathematicians in their investigations, and guard them from

spending their forces on scientifically worthless problems and

abstruse realms, a tact which is closely related to _esthetic

tact_ and which is the only thing in our science which cannot be

taught or acquired, and is yet the indispensable endowment of

every mathematician.--HANKEL, HERMANN.

_Die Entwickelung der Mathematik in den

letzten Jahrhunderten (Tübingen, 1884),

p. 21._

=623.= The mathematician requires tact and good taste at every

step of his work, and he has to learn to trust to his own

instinct to distinguish between what is really worthy of his

efforts and what is not; he must take care not to be the slave of

his symbols, but always to have before his mind the realities

which they merely serve to express. For these and other reasons

it seems to me of the highest importance that a mathematician

should be trained in no narrow school; a wide course of reading

in the first few years of his mathematical study cannot fail to

influence for good the character of the whole of his subsequent

work.--GLAISHER, J. W. L.

_Presidential Address British

Association for the Advancement of

Science, Section A, (1890); Nature, Vol.

42, p. 467._

=624.= As long as a branch of science offers an abundance of

problems, so long it is alive; a lack of problems foreshadows

extinction or the cessation of independent development.

--HILBERT, D.

_Mathematical Problems; Bulletin

American Mathematical Society, Vol. 8,

p. 438._

=625.= In mathematics as in other fields, to find one self lost

in wonder at some manifestation is frequently the half of a new

discovery.--DIRICHLET, P. G. L.

_Werke, Bd. 2 (Berlin, 1897), p. 233._

=626.= The student of mathematics often finds it hard to throw

off the uncomfortable feeling that his science, in the person of

his pencil, surpasses him in intelligence,--an impression which

the great Euler confessed he often could not get rid of. This

feeling finds a sort of justification when we reflect that the

majority of the ideas we deal with were conceived by others,

often centuries ago. In a great measure it is really the

intelligence of other people that confronts us in science.

--MACH, ERNST.

_Popular Scientific Lectures (Chicago,

1910), p. 196._

=627.= It is probably this fact [referring to the circumstance

that the problems of the parallel axiom, the squaring of the

circle, the solution of the equation of the fifth degree, have

finally found fully satisfactory and rigorous solutions] along

with other philosophical reasons that gives rise to the

conviction (which every mathematician shares, but which no one

has yet supported by proof) that every definite mathematical

problem must necessarily be susceptible of an exact settlement,

either in the form of an actual answer to the question asked, or

by the proof of the impossibility of its solution and therewith

the necessary failure of all attempts.... This conviction of the

solvability of every mathematical problem is a powerful incentive

to the worker. We hear within us the perpetual call: There is the

problem. Seek its solution. You can find it by pure reason, for

in mathematics there is no _ignorabimus_.--HILBERT, D.

_Mathematical Problems; Bulletin

American Mathematical Society, Vol. 8,

pp. 444-445._

=628.= He who seeks for methods without having a definite problem

in mind seeks for the most part in vain.--HILBERT, D.

_Mathematical Problems; Bulletin

American Mathematical Society, Vol. 8,

p. 444._

=629.= A mathematical problem should be difficult in order to

entice us, yet not completely inaccessible, lest it mock at our

efforts. It should be to us a guide post on the mazy paths to

hidden truths, and ultimately a reminder of our pleasure in the

successful solution.--HILBERT, D.

_Mathematical Problems; Bulletin

American Mathematical Society, Vol. 8,

p. 438._

=630.= The great mathematicians have acted on the principle

“_Divinez avant de demontrer_,” and it is certainly true that

almost all important discoveries are made in this fashion.

--KASNER, EDWARD.

_The Present Problems in Geometry;

Bulletin American Mathematical Society,

Vol. 11, p. 285._

=631.= “Divide _et impera_” is as true in algebra as in

statecraft; but no less true and even more fertile is the maxim

“auge _et impera_.” The more to do or to prove, the easier the

doing or the proof.--SYLVESTER, J. J.

_Proof of the Fundamental Theorem of

Invariants; Philosophic Magazine (1878),

p. 186; Collected Mathematical Papers,

Vol. 3, p. 126._

=632.= As in the domains of practical life so likewise in science

there has come about a division of labor. The individual can no

longer control the whole field of mathematics: it is only

possible for him to master separate parts of it in such a manner

as to enable him to extend the boundaries of knowledge by

creative research.--LAMPE, E.

_Die reine Mathematik in den Jahren

1884-1899, p. 10._

=633.= With the extension of mathematical knowledge will it not

finally become impossible for the single investigator to embrace

all departments of this knowledge? In answer let me point out how

thoroughly it is ingrained in mathematical science that every

real advance goes hand in hand with the invention of sharper

tools and simpler methods which at the same time assist in

understanding earlier theories and to cast aside some more

complicated developments. It is therefore possible for the

individual investigator, when he makes these sharper tools and

simpler methods his own, to find his way more easily in the

various branches of mathematics than is possible in any other

science.--HILBERT, D.

_Mathematical Problems; Bulletin

American Mathematical Society, Vol. 8,

p. 479._

=634.= It would seem at first sight as if the rapid expansion of

the region of mathematics must be a source of danger to its

future progress. Not only does the area widen but the subjects

of study increase rapidly in number, and the work of the

mathematician tends to become more and more specialized. It is,

of course, merely a brilliant exaggeration to say that no

mathematician is able to understand the work of any other

mathematician, but it is certainly true that it is daily becoming

more and more difficult for a mathematician to keep himself

acquainted, even in a general way, with the progress of any of

the branches of mathematics except those which form the field of

his own labours. I believe, however, that the increasing extent

of the territory of mathematics will always be counteracted by

increased facilities in the means of communication. Additional

knowledge opens to us new principles and methods which may

conduct us with the greatest ease to results which previously

were most difficult of access; and improvements in notation may

exercise the most powerful effects both in the simplification and

accessibility of a subject. It rests with the worker in

mathematics not only to explore new truths, but to devise the

language by which they may be discovered and expressed; and the

genius of a great mathematician displays itself no less in the

notation he invents for deciphering his subject than in the

results attained.... I have great faith in the power of

well-chosen notation to simplify complicated theories and to

bring remote ones near and I think it is safe to predict that the

increased knowledge of principles and the resulting improvements

in the symbolic language of mathematics will always enable us to

grapple satisfactorily with the difficulties arising from the

mere extent of the subject.--GLAISHER, J. W. L.

_Presidential Address British

Association for the Advancement of

Science, Section A., (1890), Nature,

Vol. 42, p. 466._

=635.= Quite distinct from the theoretical question of the manner

in which mathematics will rescue itself from the perils to which

it is exposed by its own prolific nature is the practical problem

of finding means of rendering available for the student the

results which have been already accumulated, and making it

possible for the learner to obtain some idea of the present state

of the various departments of mathematics.... The great mass of

mathematical literature will be always contained in Journals and

Transactions, but there is no reason why it should not be

rendered far more useful and accessible than at present by means

of treatises or higher text-books. The whole science suffers from

want of avenues of approach, and many beautiful branches of

mathematics are regarded as difficult and technical merely

because they are not easily accessible.... I feel very strongly

that any introduction to a new subject written by a competent

person confers a real benefit on the whole science. The number of

excellent text-books of an elementary kind that are published in

this country makes it all the more to be regretted that we have

so few that are intended for the advanced student. As an example

of the higher kind of text-book, the want of which is so badly

felt in many subjects, I may mention the second part of Prof.

Chrystal’s “Algebra” published last year, which in a small

compass gives a great mass of valuable and fundamental knowledge

that has hitherto been beyond the reach of an ordinary student,

though in reality lying so close at hand. I may add that in any

treatise or higher text-book it is always desirable that

references to the original memoirs should be given, and, if

possible, short historic notices also. I am sure that no subject

loses more than mathematics by any attempt to dissociate it from

its history.--GLAISHER, J. W. L.

_Presidential Address British

Association for the Advancement of

Science, Section A (1890); Nature, Vol.

42, p. 466._

=636.= The more a science advances, the more will it be possible

to understand immediately results which formerly could be

demonstrated only by means of lengthy intermediate considerations:

a mathematical subject cannot be considered as finally completed

until this end has been attained.--GORDAN, PAUL.

_Formensystem binärer Formen (Leipzig,

1875), p. 2._

=637.= An old French geometer used to say that a mathematical

theory was never to be considered complete till you had made it

so clear that you could explain it to the first man you met in

the street.--SMITH, H. J. S.

_Nature, Vol. 8 (1873), p. 452._

=638.= In order to comprehend and fully control arithmetical

concepts and methods of proof, a high degree of abstraction is

necessary, and this condition has at times been charged against

arithmetic as a fault. I am of the opinion that all other fields

of knowledge require at least an equally high degree of

abstraction as mathematics,--provided, that in these fields the

foundations are also everywhere examined with the rigour and

completeness which is actually necessary.--HILBERT, D.

_Die Theorie der algebraischen

Zahlkorper, Vorwort; Jahresbericht der

Deutschen Mathematiker Vereinigung, Bd.

4._

=639.= The anxious precision of modern mathematics is necessary

for accuracy, ... it is necessary for research. It makes for

clearness of thought and for fertility in trying new combinations

of ideas. When the initial statements are vague and slipshod, at

every subsequent stage of thought, common sense has to step in to

limit applications and to explain meanings. Now in creative

thought common sense is a bad master. Its sole criterion for

judgment is that the new ideas shall look like the old ones, in

other words it can only act by suppressing originality.

--WHITEHEAD, A. N.

_Introduction to Mathematics (New York,

1911), p. 157._

=640.= Mathematicians attach great importance to the elegance of

their methods and their results. This is not pure dilettantism.

What is it indeed that gives us the feeling of elegance in a

solution, in a demonstration? It is the harmony of the diverse

parts, their symmetry, their happy balance; in a word it is all

that introduces order, all that gives unity, that permits us to

see clearly and to comprehend at once both the _ensemble_ and the

details. But this is exactly what yields great results, in fact

the more we see this aggregate clearly and at a single glance,

the better we perceive its analogies with other neighboring

objects, consequently the more chances we have of divining the

possible generalizations. Elegance may produce the feeling of the

unforeseen by the unexpected meeting of objects we are not

accustomed to bring together; there again it is fruitful, since

it thus unveils for us kinships before unrecognized. It is

fruitful even when it results only from the contrast between the

simplicity of the means and the complexity of the problem set; it

makes us then think of the reason for this contrast and very

often makes us see that chance is not the reason; that it is to

be found in some unexpected law. In a word, the feeling of

mathematical elegance is only the satisfaction due to any

adaptation of the solution to the needs of our mind, and it is

because of this very adaptation that this solution can be for us

an instrument. Consequently this esthetic satisfaction is bound

up with the economy of thought.--POINCARÉ, H.

_The Future of Mathematics; Monist, Vol.

20, p. 80. [Halsted]._

=641.= The importance of a result is largely relative, is judged

differently by different men, and changes with the times and

circumstances. It has often happened that great importance has

been attached to a problem merely on account of the difficulties

which it presented; and indeed if for its solution it has been

necessary to invent new methods, noteworthy artifices, etc., the

science has gained more perhaps through these than through the

final result. In general we may call important all investigations

relating to things which in themselves are important; all those

which have a large degree of generality, or which unite under a

single point of view subjects apparently distinct, simplifying

and elucidating them; all those which lead to results that

promise to be the source of numerous consequences; etc.

--SEGRE, CORRADI.

_Some Recent Tendencies in Geometric

Investigations. Rivista di Matematica,

Vol. 1, p. 44. Bulletin American

Mathematical Society, 1904, p. 444.

[Young, J. W.]._

=642.= Geometric writings are not rare in which one would seek in

vain for an idea at all novel, for a result which sooner or later

might be of service, for anything in fact which might be

destined to survive in the science; and one finds instead

treatises on trivial problems or investigations on special forms

which have absolutely no use, no importance, which have their

origin not in the science itself but in the caprice of the

author; or one finds applications of known methods which have

already been made thousands of times; or generalizations from

known results which are so easily made that the knowledge of the

latter suffices to give at once the former. Now such work is not

merely useless; it is actually harmful because it produces a real

incumbrance in the science and an embarrassment for the more

serious investigators; and because often it crowds out certain

lines of thought which might well have deserved to be studied.

--SEGRE, CORRADI.

_On some Recent Tendencies in Geometric

Investigations; Rivista di Matematica,

1891, p. 43. Bulletin American

Mathematical Society, 1904, p. 443

[Young, J. W.]._

=643.= A student who wishes now-a-days to study geometry by

dividing it sharply from analysis, without taking account of the

progress which the latter has made and is making, that student no

matter how great his genius, will never be a whole geometer. He

will not possess those powerful instruments of research which

modern analysis puts into the hands of modern geometry. He will

remain ignorant of many geometrical results which are to be

found, perhaps implicitly, in the writings of the analyst. And

not only will he be unable to use them in his own researches, but

he will probably toil to discover them himself, and, as happens

very often, he will publish them as new, when really he has only

rediscovered them.--SEGRE, CORRADI.

_On some recent Tendencies in

Geometrical Investigations; Rivista di

Matematica, 1891, p. 43. Bulletin

American Mathematical Society, 1904, p.

443 [Young, J. W.]._

=644.= Research may start from definite problems whose importance

it recognizes and whose solution is sought more or less directly

by all forces. But equally legitimate is the other method of

research which only selects the field of its activity and,

contrary to the first method, freely reconnoitres in the search

for problems which are capable of solution. Different individuals

will hold different views as to the relative value of these two

methods. If the first method leads to greater penetration it is

also easily exposed to the danger of unproductivity. To the second

method we owe the acquisition of large and new fields, in which

the details of many things remain to be determined and explored by

the first method.--CLEBSCH, A.

_Zum Gedächtniss an Julius Plücker;

Göttinger Abhandlungen, 16, 1871,

Mathematische Classe, p. 6._

=645.= During a conversation with the writer in the last weeks of

his life, _Sylvester_ remarked as curious that notwithstanding he

had always considered the bent of his mind to be rather

analytical than geometrical, he found in nearly every case that

the solution of an analytical problem turned upon some quite

simple geometrical notion, and that he was never satisfied until

he could present the argument in geometrical language.

--MACMAHON, P. A.

_Proceedings London Royal Society, Vol.

63, p. 17._

=646.= The origin of a science is usually to be sought for not in

any systematic treatise, but in the investigation and solution of

some particular problem. This is especially the case in the

ordinary history of the great improvements in any department of

mathematical science. Some problem, mathematical or physical, is

proposed, which is found to be insoluble by known methods. This

condition of insolubility may arise from one of two causes:

Either there exists no machinery powerful enough to effect the

required reduction, or the workmen are not sufficiently expert to

employ their tools in the performance of an entirely new piece of

work. The problem proposed is, however, finally solved, and in

its solution some new principle, or new application of old

principles, is necessarily introduced. If a principle is brought

to light it is soon found that in its application it is not

necessarily limited to the particular question which occasioned

its discovery, and it is then stated in an abstract form and

applied to problems of gradually increasing generality.

Other principles, similar in their nature, are added, and the

original principle itself receives such modifications and

extensions as are from time to time deemed necessary. The same

is true of new applications of old principles; the application is

first thought to be merely confined to a particular problem, but

it is soon recognized that this problem is but one, and generally

a very simple one, out of a large class, to which the same

process of investigation and solution are applicable. The result

in both of these cases is the same. A time comes when these

several problems, solutions, and principles are grouped together

and found to produce an entirely new and consistent method; a

nomenclature and uniform system of notation is adopted, and the

principles of the new method become entitled to rank as a

distinct science.--CRAIG, THOMAS.

_A Treatise on Projection, Preface. U.

S. Coast and Geodetic Survey, Treasury

Department Document, No. 61._

=647.= The aim of research is the discovery of the equations

which subsist between the elements of phenomena.--MACH, ERNST.

_Popular Scientific Lectures (Chicago,

1910), p. 205._

=648.= Let him [the author] be permitted also in all humility to

add ... that in consequence of the large arrears of algebraical

and arithmetical speculations waiting in his mind their turn to

be called into outward existence, he is driven to the alternative

of leaving the fruits of his meditations to perish (as has been

the fate of too many foregone theories, the still-born progeny of

his brain, now forever resolved back again into the primordial

matter of thought), or venturing to produce from time to time

such imperfect sketches as the present, calculated to evoke the

mental co-operation of his readers, in whom the algebraical

instinct has been to some extent developed, rather than to

satisfy the strict demands of rigorously systematic exposition.

--SYLVESTER, J. J.

_Philosophic Magazine (1863), p. 460._

=649.= In other branches of science, where quick publication

seems to be so much desired, there may possibly be some excuse

for giving to the world slovenly or ill-digested work, but there

is no such excuse in mathematics. The form ought to be as

perfect as the substance, and the demonstrations as rigorous as

those of Euclid. The mathematician has to deal with the most

exact facts of Nature, and he should spare no effort to render

his interpretation worthy of his subject, and to give to his work

its highest degree of perfection. “_Pauca sed matura_” was

Gauss’s motto.--GLAISHER, J. W. L.

_Presidential Address British

Association for the Advancement of

Science, Section A, (1890); Nature, Vol.

42, p. 467._

=650.= It is the man not the method that solves the problem.

--MASCHKE, H.

_Present Problems of Algebra and

Analysis; Congress of Arts and Sciences

(New York and Boston, 1905), Vol. 1, p.

530._

=651.= Today it is no longer questioned that the principles of

the analysts are the more far-reaching. Indeed, the synthesists

lack two things in order to engage in a general theory of

algebraic configurations: these are on the one hand a definition

of imaginary elements, on the other an interpretation of general

algebraic concepts. Both of these have subsequently been

developed in synthetic form, but to do this the essential

principle of synthetic geometry had to be set aside. This

principle which manifests itself so brilliantly in the theory of

linear forms and the forms of the second degree, is the

possibility of immediate proof by means of visualized

constructions.--KLEIN, FELIX.

_Riemannsche Flächen (Leipzig, 1906),

Bd. 1, p. 234._

=652.= Abstruse mathematical researches ... are ... often abused for

having no obvious physical application. The fact is that the most

useful parts of science have been investigated for the sake of

truth, and not for their usefulness. A new branch of mathematics,

which has sprung up in the last twenty years, was denounced by the

Astronomer Royal before the University of Cambridge as doomed to

be forgotten, on account of its uselessness. Now it turns out that

the reason why we cannot go further in our investigations of

molecular action is that we do not know enough of this branch of

mathematics.--CLIFFORD, W. K.

_Conditions of Mental Development;

Lectures and Essays (London, 1901), Vol.

1, p. 115._

=653.= In geometry, as in most sciences, it is very rare that an

isolated proposition is of immediate utility. But the theories

most powerful in practice are formed of propositions which

curiosity alone brought to light, and which long remained useless

without its being able to divine in what way they should one day

cease to be so. In this sense it may be said, that in real

science, no theory, no research, is in effect useless.--VOLTAIRE.

_A Philosophical Dictionary, Article

“Geometry”; (Boston, 1881), Vol. 1, p.

374._

=654.= Scientific subjects do not progress necessarily on the

lines of direct usefulness. Very many applications of the

theories of pure mathematics have come many years, sometimes

centuries, after the actual discoveries themselves. The weapons

were at hand, but the men were not able to use them.

--FORSYTH, A. R.

_Perry’s Teaching of Mathematics

(London, 1902), p. 35._

=655.= It is no paradox to say that in our most theoretical moods

we may be nearest to our most practical applications.

--WHITEHEAD, A. N.

_Introduction to Mathematics (New York),

p. 100._

=656.= Although with the majority of those who study and practice

in these capacities [engineers, builders, surveyors, geographers,

navigators, hydrographers, astronomers], second-hand acquirements,

trite formulas, and appropriate tables are sufficient for ordinary

purposes, yet these trite formulas and familiar rules were

originally or gradually deduced from the profound investigations

of the most gifted minds, from the dawn of science to the present

day.... The further developments of the science, with its possible

applications to larger purposes of human utility and grander

theoretical generalizations, is an achievement reserved for a few

of the choicest spirits, touched from time to time by Heaven to

these highest issues. The intellectual world is filled with latent

and undiscovered truth as the material world is filled with latent

electricity.--EVERETT, EDWARD.

_Orations and Speeches, Vol. 3 (Boston,

1870), p. 513._

=657.= If we view mathematical speculations with reference to

their use, it appears that they should be divided into two

classes. To the first belong those which furnish some marked

advantage either to common life or to some art, and the value of

such is usually determined by the magnitude of this advantage.

The other class embraces those speculations which, though

offering no direct advantage, are nevertheless valuable in that

they extend the boundaries of analysis and increase our resources

and skill. Now since many investigations, from which great

advantage may be expected, must be abandoned solely because of

the imperfection of analysis, no small value should be assigned

to those speculations which promise to enlarge the field of

analysis.--EULER.

_Novi Comm. Petr., Vol. 4, Preface._

=658.= The discovery of the conic sections, attributed to Plato,

first threw open the higher species of form to the contemplation

of geometers. But for this discovery, which was probably regarded

in Plato’s time and long after him, as the unprofitable amusement

of a speculative brain, the whole course of practical philosophy

of the present day, of the science of astronomy, of the theory

of projectiles, of the art of navigation, might have run in

a different channel; and the greatest discovery that has ever

been made in the history of the world, the law of universal

gravitation, with its innumerable direct and indirect consequences

and applications to every department of human research and

industry, might never to this hour have been elicited.

--SYLVESTER, J. J.

_A Probationary Lecture on Geometry;

Collected Mathematical Papers, Vol. 2

(Cambridge, 1908), p. 7._

=659.= No more impressive warning can be given to those who would

confine knowledge and research to what is apparently useful, than

the reflection that conic sections were studied for eighteen

hundred years merely as an abstract science, without regard to

any utility other than to satisfy the craving for knowledge on

the part of mathematicians, and that then at the end of this long

period of abstract study, they were found to be the necessary

key with which to attain the knowledge of the most important laws

of nature.--WHITEHEAD, A. N.

_Introduction to Mathematics (New York,

York, 1911), pp. 136-137._

=660.= The Greeks in the first vigour of their pursuit of

mathematical truth, at the time of Plato and soon after, had by

no means confined themselves to those propositions which had a

visible bearing on the phenomena of nature; but had followed out

many beautiful trains of research concerning various kinds of

figures, for the sake of their beauty alone; as for instance in

their doctrine of Conic Sections, of which curves they had

discovered all the principal properties. But it is curious to

remark, that these investigations, thus pursued at first as mere

matters of curiosity and intellectual gratification, were

destined, two thousand years later, to play a very important part

in establishing that system of celestial motions which succeeded

the Platonic scheme of cycles and epicycles. If the properties of

conic sections had not been demonstrated by the Greeks and thus

rendered familiar to the mathematicians of succeeding ages,

Kepler would probably not have been able to discover those laws

respecting the orbits and motions of planets which were the

occasion of the greatest revolution that ever happened in the

history of science.--WHEWELL, W.

_History of Scientific Ideas, Bk. 2,

chap. 14, sect. 3._

=661.= The greatest mathematicians, as Archimedes, Newton, and

Gauss, always united theory and applications in equal measure.

--KLEIN, FELIX.

_Elementarmathematik vom höheren

Standpunkte aus (Leipzig, 1909), Bd. 2,

p. 392._

=662.= We may see how unexpectedly recondite parts of pure

mathematics may bear upon physical science, by calling to mind

the circumstance that Fresnel obtained one of the most curious

confirmations of the theory (the laws of Circular Polarization by

reflection) through an interpretation of an algebraical

expression, which, according to the original conventional meaning

of the symbols, involved an impossible quantity.--WHEWELL, W.

_History of Scientific Ideas, Bk. 2,

chap. 14, sect. 8._

=663.= A great department of thought must have its own inner life,

however transcendent may be the importance of its relations to the

outside. No department of science, least of all one requiring so

high a degree of mental concentration as Mathematics, can be

developed entirely, or even mainly, with a view to applications

outside its own range. The increased complexity and specialisation

of all branches of knowledge makes it true in the present, however

it may have been in former times, that important advances in such

a department as Mathematics can be expected only from men who are

interested in the subject for its own sake, and who, whilst

keeping an open mind for suggestions from outside, allow their

thought to range freely in those lines of advance which are

indicated by the present state of their subject, untrammelled by

any preoccupation as to applications to other departments of

science. Even with a view to applications, if Mathematics is to be

adequately equipped for the purpose of coping with the intricate

problems which will be presented to it in the future by Physics,

Chemistry and other branches of physical science, many of these

problems probably of a character which we cannot at present

forecast, it is essential that Mathematics should be allowed to

develop freely on its own lines.--HOBSON, E. W.

_Presidential Address British

Association for the Advancement of

Science, Section A, (1910); Nature, Vol.

84, p. 286._

=664.= To emphasize this opinion that mathematicians would be

unwise to accept practical issues as the sole guide or the chief

guide in the current of their investigations, ... let me take one

more instance, by choosing a subject in which the purely

mathematical interest is deemed supreme, the theory of functions

of a complex variable. That at least is a theory in pure

mathematics, initiated in that region, and developed in that

region; it is built up in scores of papers, and its plan

certainly has not been, and is not now, dominated or guided by

considerations of applicability to natural phenomena. Yet what

has turned out to be its relation to practical issues? The

investigations of Lagrange and others upon the construction of

maps appear as a portion of the general property of conformal

representation; which is merely the general geometrical method

of regarding functional relations in that theory. Again, the

interesting and important investigations upon discontinuous

two-dimensional fluid motion in hydrodynamics, made in the last

twenty years, can all be, and now are all, I believe, deduced

from similar considerations by interpreting functional relations

between complex variables. In the dynamics of a rotating heavy

body, the only substantial extension of our knowledge since the

time of Lagrange has accrued from associating the general

properties of functions with the discussion of the equations of

motion. Further, under the title of conjugate functions, the

theory has been applied to various questions in electrostatics,

particularly in connection with condensors and electrometers.

And, lastly, in the domain of physical astronomy, some of the

most conspicuous advances made in the last few years have been

achieved by introducing into the discussion the ideas, the

principles, the methods, and the results of the theory of

functions ... the refined and extremely difficult work of

Poincaré and others in physical astronomy has been possible only

by the use of the most elaborate developments of some purely

mathematical subjects, developments which were made without a

thought of such applications.--FORSYTH, A. R.

_Presidential Address British

Association for the Advancement of

Science, Section A, (1897); Nature, Vol.

56, p. 377._

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