place in which the very stones testify to that progress--in the town of
Watt and of Boulton. I will only remark, in passing, that material
advancement has its share in moral and intellectual progress. Becky
Sharp's acute remark that it is not difficult to be virtuous on ten
thousand a year, has its application to nations; and it is futile to
expect a hungry and squalid population to be anything but violent and
gross. But as regards other than material welfare, although perfection
is not yet in sight--even from the mast-head--it is surely true that
things are much better than they were.
Take the upper and middle classes as a whole, and it may be said that
open immorality and gross intemperance have vanished. Four and six
bottle men are as extinct as the dodo. Women of good repute do not
gamble, and talk modelled upon Dean Swift's "Art of Polite
Conversation" would be tolerated in no decent kitchen.
Members of the legislature are not to be bought; and constituents are
awakening to the fact that votes must not be sold--even for such
trifles as rabbits and tea and cake. Political power has passed into
the hands of the masses of the people. Those whom Priestley calls their
servants have recognised their position, and have requested the master
to be so good as to go to school and fit himself for the administration
of his property. In ordinary life, no civil disability attaches to any
one on theological grounds, and high offices of the state are open to
Papist, Jew, and Secularist.
Whatever men's opinions as to the policy of Establishment, no one can
hesitate to admit that the clergy of the Church are men of pure life
and conversation, zealous in the discharge of their duties; and at
present, apparently, more bent on prosecuting one another than on
meddling with Dissenters. Theology itself has broadened so much, that
Anglican divines put forward doctrines more liberal than those of
Priestley; and, in our state-supported churches, one listener may hear
a sermon to which Bossuet might have given his approbation, while
another may hear a discourse in which Socrates would find nothing new.
But great as these changes may be, they sink into insignificance beside
the progress of physical science, whether we consider the improvement
of methods of investigation, or the increase in bulk of solid
knowledge. Consider that the labours of Laplace, of Young, of Davy, and
of Faraday; of Cuvier, of Lamarck, and of Robert Brown; of Von Baer,
and of Schwann; of Smith and of Hutton, have all been carried on since
Priestley discovered oxygen; and consider that they are now things of
the past, concealed by the industry of those who have built upon them,
as the first founders of a coral reef are hidden beneath the life's
work of their successors; consider that the methods of physical science
are slowly spreading into all investigations, and that proofs as valid
as those required by her canons of investigation are being demanded of
all doctrines which ask for men's assent; and you will have a faint
image of the astounding difference in this respect between the
nineteenth century and the eighteenth.
If we ask what is the deeper meaning of all these vast changes, I think
there can be but one reply. They mean that reason has asserted and
exercised her primacy over all provinces of human activity: that
ecclesiastical authority has been relegated to its proper place; that
the good of the governed has been finally recognised as the end of
government, and the complete responsibility of governors to the people
as its means; and that the dependence of natural phenomena in general
on the laws of action of what we call matter has become an axiom.
But it was to bring these things about, and to enforce the recognition
of these truths, that Joseph Priestley laboured. If the nineteenth
century is other and better than the eighteenth, it is, in great
measure, to him, and to such men as he, that we owe the change. If the
twentieth century is to be better than the nineteenth, it will be
because there are among us men who walk in Priestley's footsteps.
Such men are not those whom their own generation delights to honour;
such men, in fact, rarely trouble themselves about honour, but ask, in
another spirit than Falstaff's, "What is honour? Who hath it? He that
died o' Wednesday." But whether Priestley's lot be theirs, and a future
generation, in justice and in gratitude, set up their statues; or
whether their names and fame are blotted out from remembrance, their
work will live as long as time endures. To all eternity, the sum of
truth and right will have been increased by their means; to all
eternity, falsehood and injustice will be the weaker because they have
lived.
* * * * *
Footnotes:
[1] "Quasi cursores, vitai lampada tradunt."--LUCR. _De Rerum Nat_. ii.
78.
[2] _Life and Correspondence of Dr. Priestley_, by J. T. Rutt. Vol. I.
p. 50.
[3] _Autobiography_, §§ 100, 101.
[4] See _The Life of Mary Anne Schimmelpenninck_. Mrs.
Schimmelpenninck (_née_ Galton) remembered Priestley very well,
and her description of him is worth quotation:--"A man of admirable
simplicity, gentleness and kindness of heart, united with great
acuteness of intellect. I can never forget the impression produced on
me by the serene expression of his countenance. He, indeed, seemed
present with God by recollection, and with man by cheerfulness. I
remember that, in the assembly of these distinguished men, amongst whom
Mr. Boulton, by his noble manner, his fine countenance (which much
resembled that of Louis XIV.), and princely munificence, stood
pre-eminently as the great Mecaenas; even as a child, I used to feel,
when Dr. Priestley entered after him, that the glory of the one was
terrestrial, that of the other celestial; and utterly far as I am
removed from a belief in the sufficiency of Dr. Priestley's theological
creed, I cannot but here record this evidence of the eternal power of
any portion of the truth held in its vitality."
[5] Even Mrs. Priestley, who might be forgiven for regarding the
destroyers of her household gods with some asperity, contents herself,
in writing to Mrs. Barbauld, with the sarcasm that the Birmingham
people "will scarcely find so many respectable characters, a second
time, to make a bonfire of."
[6] _Experiments and Observations on Different Kinds of Air_, vol.
ii. p. 31.
[7] _Experiments and Observations on Different Kinds of Air_, vol.
ii. pp. 34, 35.
[8] _Ibid_. vol. i. p. 40.
[9] _Experiments and Observations on Different Kinds of Air_, vol. ii.
p. 48.
[10] _Ibid_. p. 55.
[11] _Ibid_. p. 60. The italics are Priestley's own.
[12] "In all the newspapers and most of the periodical publications I
was represented as an unbeliever in Revelation, and no better than an
atheist."--_Autobiography_, Rutt, vol i. p. 124. "On the walls of
houses, etc., and especially where I usually went, were to be seen, in
large characters, 'MADAN FOR EVER; DAMN PRIESTLEY; NO PRESBYTERIANISM;
DAMN THE PRESBYTERIANS,' etc., etc.; and, at one time, I was followed
by a number of boys, who left their play, repeating what they had seen
on the walls, and shouting out, '_Damn Priestley; damn him, damn
him, for ever, for ever,_' etc., etc. This was no doubt a lesson
which they had been taught by their parents, and what they, I fear, had
learned from their superiors."--_Appeal to the Public on the Subject
of the Riots at Birmingham_.
[13] First Series. _On Some of the Peculiarities of the Christian
Religion_. Essay I. "Revelation of a Future State."
[14] Not only is Priestley at one with Bishop Courtenay in this matter,
but with Hartley and Bonnet, both of them stout champions of
Christianity. Moreover, Archbishop Whately's essay is little better
than an expansion of the first paragraph of Hume's famous essay on the
Immortality of the Soul:--"By the mere light of reason it seems
difficult to prove the immortality of the soul; the arguments for it
are commonly derived either from metaphysical topics, or moral, or
physical. But it is in reality the Gospel, and the Gospel alone, that
has brought _life and immortality to light_." It is impossible to
imagine that a man of Whately's tastes and acquirements had not read
Hume or Hartley, though he refers to neither.
[15] _Essay on the First Principles of Government_, Second edition,
1771.
[16] "Utility of Establishments," in _Essay on First Principles of
Government_, 1771.
[17] In 1732 Doddridge was cited for teaching without the Bishop's
leave, at Northampton.
II
ON THE EDUCATIONAL VALUE OF THE NATURAL HISTORY SCIENCES
[1854]
The subject to which I have to beg your attention during the ensuing
hour is "The Relation of Physiological Science to other branches of
Knowledge."
Had circumstances permitted of the delivery, in their strict logical
order, of that series of discourses of which the present lecture is a
member, I should have preceded my friend and colleague Mr. Henfrey, who
addressed you on Monday last; but while, for the sake of that order, I
must beg you to suppose that this discussion of the Educational
bearings of Biology in general _does_ precede that of Special
Zoology and Botany, I am rejoiced to be able to take advantage
of the light thus already thrown upon the tendency and methods of
Physiological Science.
Regarding Physiological Science, then, in its widest sense--as the
equivalent of _Biology_--the Science of Individual Life--we have to
consider in succession:
1. Its position and scope as a branch of knowledge.
2. Its value as a means of mental discipline.
3. Its worth as practical information.
And lastly,
4. At what period it may best be made a branch of Education.
Our conclusions on the first of these heads must depend, of course,
upon the nature of the subject-matter of Biology; and I think a few
preliminary considerations will place before you in a clear light the
vast difference which exists between the living bodies with which
Physiological science is concerned, and the remainder of the
universe;--between the phaenomena of Number and Space, of Physical and
of Chemical force, on the one hand, and those of Life on the other.
The mathematician, the physicist, and the chemist contemplate things in
a condition of rest; they look upon a state of equilibrium as that to
which all bodies normally tend.
The mathematician does not suppose that a quantity will alter, or that
a given point in space will change its direction with regard to another
point, spontaneously. And it is the same with the physicist. When
Newton saw the apple fall, he concluded at once that the act of falling
was not the result of any power inherent in the apple, but that it was
the result of the action of something else on the apple. In a similar
manner, all physical force is regarded as the disturbance of an
equilibrium to which things tended before its exertion,--to which they
will tend again after its cessation.
The chemist equally regards chemical change in a body as the effect of
the action of something external to the body changed. A chemical
compound once formed would persist for ever, if no alteration took
place in surrounding conditions.
But to the student of Life the aspect of Nature is reversed. Here,
incessant, and, so far as we know, spontaneous change is the rule, rest
the exception--the anomaly to be accounted for. Living things have no
inertia, and tend to no equilibrium.
Permit me, however, to give more force and clearness to these somewhat
abstract considerations by an illustration or two.
Imagine a vessel full of water, at the ordinary temperature, in an
atmosphere saturated with vapour. The _quantity_ and the _figure_ of that
water will not change, so far as we know, for ever.
Suppose a lump of gold be thrown into the vessel--motion and
disturbance of figure exactly proportional to the momentum of the gold
will take place. But after a time the effects of this disturbance will
subside--equilibrium will be restored, and the water will return to its
passive state.
Expose the water to cold--it will solidify--and in so doing its
particles will arrange themselves in definite crystalline shapes. But
once formed, these crystals change no further.
Again, substitute for the lump of gold some substance capable of
entering into chemical relations with the water:--say, a mass of that
substance which is called "protein"--the substance of flesh:--a very
considerable disturbance of equilibrium will take place--all sorts of
chemical compositions and decompositions will occur; but in the end, as
before, the result will be the resumption of a condition of rest.
Instead of such a mass of _dead_ protein, however, take a particle of
_living_ protein--one of those minute microscopic living things which
throng our pools, and are known as Infusoria--such a creature, for
instance, as an Euglena, and place it in our vessel of water. It is
a round mass provided with a long filament, and except in this
peculiarity of shape, presents no appreciable physical or chemical
difference whereby it might be distinguished from the particle of dead
protein.
But the difference in the phaenomena to which it will give rise is
immense: in the first place it will develop a vast quantity of physical
force--cleaving the water in all directions with considerable rapidity
by means of the vibrations of the long filament or cilium.
Nor is the amount of chemical energy which the little creature
possesses less striking. It is a perfect laboratory in itself, and it
will act and react upon the water and the matters contained therein;
converting them into new compounds resembling its own substance, and at
the same time giving up portions of its own substance which have become
effete.
Furthermore, the Euglena will increase in size; but this increase is by
no means unlimited, as the increase of a crystal might be. After it has
grown to a certain extent it divides, and each portion assumes the form
of the original, and proceeds to repeat the process of growth and
division.
Nor is this all. For after a series of such divisions and subdivisions,
these minute points assume a totally new form, lose their long
tails--round themselves, and secrete a sort of envelope or box, in
which they remain shut up for a time, eventually to resume, directly or
indirectly, their primitive mode of existence.
Now, so far as we know, there is no natural limit to the existence of
the Euglena, or of any other living germ. A living species once
launched into existence tends to live for ever.
Consider how widely different this living particle is from the dead
atoms with which the physicist and chemist have to do!
The particle of gold falls to the bottom and rests--the particle of
dead protein decomposes and disappears--it also rests: but the
_living_ protein mass neither tends to exhaustion of its forces nor
to any permanency of form, but is essentially distinguished as a
disturber of equilibrium so far as force is concerned,--as undergoing
continual metamorphosis and change, in point of form.
Tendency to equilibrium of force and to permanency of form, then, are
the characters of that portion of the universe which does not live--the
domain of the chemist and physicist.
Tendency to disturb existing equilibrium--to take on forms which
succeed one another in definite cycles--is the character of the living
world.
What is the cause of this wonderful difference between the dead
particle and the living particle of matter appearing in other respects
identical? that difference to which we give the name of Life?
I, for one, cannot tell you. It may be that, by and by, philosophers
will discover some higher laws of which the facts of life are
particular cases--very possibly they will find out some bond between
physico-chemical phaenomena on the one hand, and vital phaenomena on
the other. At present, however, we assuredly know of none; and I think
we shall exercise a wise humility in confessing that, for us at least,
this successive assumption of different states--(external conditions
remaining the same)--this _spontaneity of action_--if I may use a term
which implies more than I would be answerable for--which constitutes
so vast and plain a practical distinction between living bodies and
those which do not live, is an ultimate fact; indicating as such, the
existence of a broad line of demarcation between the subject-matter
of Biological and that of all other sciences.
For I would have it understood that this simple Euglena is the type of
_all_ living things, so far as the distinction between these and
inert matter is concerned. That cycle of changes, which is constituted
by perhaps not more than two or three steps in the Euglena, is as
clearly manifested in the multitudinous stages through which the germ
of an oak or of a man passes. Whatever forms the Living Being may take
on, whether simple or complex, _production, growth, reproduction,_ are
the phaenomena which distinguish it from that which does not live.
If this be true, it is clear that the student, in passing from the
physico-chemical to the physiological sciences, enters upon a totally
new order of facts; and it will next be for us to consider how far
these new facts involve _new_ methods, or require a modification of
those with which he is already acquainted. Now a great deal is said
about the peculiarity of the scientific method in general, and of the
different methods which are pursued in the different sciences. The
Mathematics are said to have one special method; Physics another,
Biology a third, and so forth. For my own part, I must confess that I
do not understand this phraseology.
So far as I can arrive at any clear comprehension of the matter,
Science is not, as many would seem to suppose, a modification of the
black art, suited to the tastes of the nineteenth century, and
flourishing mainly in consequence of the decay of the Inquisition.
Science is, I believe, nothing but _trained and organised common
sense_, differing from the latter only as a veteran may differ from
a raw recruit: and its methods differ from those of common sense only
so far as the guardsman's cut and thrust differ from the manner in
which a savage wields his club. The primary power is the same in each
case, and perhaps the untutored savage has the more brawny arm of
the two. The _real_ advantage lies in the point and polish of the
swordsman's weapon; in the trained eye quick to spy out the weakness of
the adversary; in the ready hand prompt to follow it on the instant.
But, after all, the sword exercise is only the hewing and poking of the
clubman developed and perfected.
So, the vast results obtained by Science are won by no mystical
faculties, by no mental processes, other than those which are practised
by every one of us, in the humblest and meanest affairs of life. A
detective policeman discovers a burglar from the marks made by his
shoe, by a mental process identical with that by which Cuvier restored
the extinct animals of Montmartre from fragments of their bones. Nor
does that process of induction and deduction by which a lady, finding a
stain of a peculiar kind upon her dress, concludes that somebody has
upset the inkstand thereon, differ in any way, in kind, from that by
which Adams and Leverrier discovered a new planet.
The man of science, in fact, simply uses with scrupulous exactness the
methods which we all, habitually and at every moment, use carelessly;
and the man of business must as much avail himself of the scientific
method--must be as truly a man of science--as the veriest bookworm of
us all; though I have no doubt that the man of business will find
himself out to be a philosopher with as much surprise as M. Jourdain
exhibited vhen he discovered that he had been all his life talking
prose. If, however, there be no real difference between the methods of
science and those of common life, it would seem, on the face of the
matter, highly improbable that there should be any difference between
the methods of the different sciences; nevertheless, it is constantly
taken for granted that there is a very wide difference between the
Physiological and other sciences in point of method.
In the first place it is said--and I take this point first, because the
imputation is too frequently admitted by Physiologists themselves--that
Biology differs from the Physico-chemical and Mathematical sciences in
being "inexact."
Now, this phrase "inexact" must refer either to the _methods_ or to
the _results_ of Physiological science.
It cannot be correct to apply it to the methods; for, as I hope to show
you by and by, these are identical in all sciences, and whatever is
true of Physiological method is true of Physical and Mathematical
method.
Is it then the _results_ of Biological science which are "inexact"?
I think not. If I say that respiration is performed by the
lungs; that digestion is effected in the stomach; that the eye is the
organ of sight; that the jaws of a vertebrated animal never open
sideways, but always up and down; while those of an annulose animal
always open sideways, and never up and down--I am enumerating
propositions which are as exact as anything in Euclid. How then has
this notion of the inexactness of Biological science come about? I
believe from two causes: first, because in consequence of the great
complexity of the science and the multitude of interfering conditions,
we are very often only enabled to predict approximately what will occur
under given circumstances; and secondly, because, on account of the
comparative youth of the Physiological sciences, a great many of their
laws are still imperfectly worked out. But, in an educational point of
view, it is most important to distinguish between the essence of a
science and the accidents which surround it; and essentially, the
methods and results of Physiology are as exact as those of Physics or
Mathematics.
It is said that the Physiological method is especially _comparative_;
[1] and this dictum also finds favour in the eyes of many.
I should be sorry to suggest that the speculators on scientific
classification have been misled by the accident of the name of one
leading branch of Biology--_Comparative Anatomy_; but I would ask
whether _comparison_, and that classification which is the result of
comparison, are not the essence of every science whatsoever? How is it
possible to discover a relation of cause and effect of _any_ kind
without comparing a series of cases together in which the supposed
cause and effect occur singly, or combined? So far from comparison
being in any way peculiar to Biological science, it is, I think, the
essence of every science.
A speculative philosopher again tells us that the Biological
sciences are distinguished by being sciences of observation and not
of experiment! [2] Of all the strange assertions into which speculation
without practical acquaintance with a subject may lead even an able
man, I think this is the very strangest. Physiology not an experimental
science? Why, there is not a function of a single organ in the body
which has not been determined wholly and solely by experiment? How did
Harvey determine the nature of the circulation, except by experiment?
How did Sir Charles Bell determine the functions of the roots of the
spinal nerves, save by experiment? How do we know the use of a nerve at
all, except by experiment? Nay, how do you know even that your eye is
your seeing apparatus, unless you make the experiment of shutting it;
or that your ear is your hearing apparatus, unless you close it up and
thereby discover that you become deaf?
It would really be much more true to say that Physiology is _the_
experimental science _par excellence_ of all sciences; that in which
there is least to be learnt by mere observation, and that which
affords the greatest field for the exercise of those faculties which
characterise the experimental philosopher. I confess, if any one were
to ask me for a model application of the logic of experiment, I should
know no better work to put into his hands than Bernard's late
Researches on the Functions of the Liver. [3]
Not to give this lecture a too controversial tone, however, I must
only advert to one more doctrine, held by a thinker of our own age
and country, whose opinions are worthy of all respect. It is, that
the Biological sciences differ from all others, inasmuch as in _them_
classification takes place by type and not by definition. [4]