September 7,1872.] THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
1S5 
of gravitation. That seems that the motion of the body 
may be resolved into a motion of every one of its par¬ 
ticles towards every one of the particles of the earth, 
with an acceleration inversely as the square of the dis¬ 
tance between them. But this attraction of two par¬ 
ticles must always, I think, be less familiar than the 
original falling body, however early the children of the 
future begin to read their Newton. Can the attraction 
itself be explained ? Le Sage said that there is an ever- 
astmg hail of innumerable small ether-particles from 
all sides, and that the two material particles shield each 
other from this and so get pushed together. This is an 
explanation; it may or may not be a true one. The 
attraction may be an ultimate simple fact; or it may be 
made up of simple facts utterly unlike anything that 
we know at present; and in either of these cases there 
no ® x P la ^ at i° n * We have no right to conclude, then, 
that the order of events is always capable of beimr ex¬ 
plained. ° 
There is yet another way in which it is said that 
nature is reasonable ; namely, inasmuch as every effect 
has a cause. AVhat do we mean by this ? 
In asking this question we have entered upon an ap¬ 
palling task. The word represented by cause has sixty- 
tour meanings in Plato and forty-eight in Aristotle. 
■" e ® e '(^ere men who liked to know as near as might be 
vhat they meant; but how many meanings it has had 
in the writings of the myriads of people wdio have not 
tried to know what they meant by it will, I hope, never 
be counted. It would not only be the height of pre- 
sumption in me to attempt to fix the meaning of a 
woid which has been used by so grave authority in so 
man} and ■s arious senses ; but it would seem a thankless 
task to do that once more which has been done so 
o ten at sundry times and in divers manners before. 
j et without this we cannot determine what we 
niean by saying that the order of nature is reasonable. 
1 shall evade the difficulty by telling you Mr. Grote’s 
opinion. _ lou come to a scarecrow and ask, what is the 
causu of this . lou find that a man made it to frighten 
the birds. You go away and say to yourself, “ Every¬ 
thing,resembles this scarecrow. Everything has a pur¬ 
pose. And from that day the word cause means for 
you what Aristotle meant by final cause. Or you o-o 
into a hairdresser s shop, and wonder what turns the 
wheel to which the rotary brush is attached. On inves¬ 
tigating other parts of the premises you find a man 
working’away at a handle. Then you go away and say, 
verythmg is like that wheel. If I investigated 
enough, I should always find a man at a handle.” And 
the man at the handle, or whatever corresponds to him, 
is from henceforth known to you as cause , and so gene- 
ra ly. when you have made out any sequence of events 
to your entire satisfaction, so that you know all about 
it, the laws involved being so familiar that you seem 
to see how the beginning must have been followed by 
the end; then you apply that as a simile to other events 
whatever, and your idea of cause is determined by it. 
Only when a case arises, as it always must, to which 
the simile will not apply, you do not confess to your- 
seit that it was only a simile and need not apply to 
e\ eij. thing, but you say, “The causeofthat event is amys- 
tery which must remain for ever unknown to me.” On 
equally just grounds, the nervous system of my um¬ 
brella is a mystery which must remain for ever unknown 
to me. My umbrella has no nervous system; and the 
event to which your simile did not apply has no cause 
in your sense of the word. When we say then that 
every efiect has a cause, we mean that every event is 
connected with something in a way that might make 
somebody call that the cause of it. But I at least have 
ncv . e J seen any single meaning of the word that 
could be. fairly applied to the whole order of nature. 
± rom this remark I cannot even accept an attempt re¬ 
cently made by Mr. Bain to give the word a universal 
meaning, though I desire to speak of that attempt with 
the greatest respect. Mr. Bain wishes to make the word 
cause hang on in some way to what we call the law of 
energy; but though I speak with great diffidence, I do 
think a careful consideration will show that the intro¬ 
duction of this word cause can only bring confusion into 
a matter which is distinct and clear enough to those who 
have taken the trouble to understand what energy means. 
It would be impossible to explain that this evening; but 
I may mention that energy is a technical term out of 
mathematical physics, which requires of most men a good 
deal of careful study to understand it accurately. 
Let us pass on to consider with all the reverence 
which it demands another opinion, held by great num¬ 
bers of the philosophers who have lived in the brightening 
ages of Europe; the opinion that at the basis of the 
natural order there is something which we can know to 
be unreasonable , to evade the processes of human thought. 
The opinion is set forth first by Kant, so far as I know, 
in the form of his famous doctrine of the antinomies or 
contradictions, the nature of which I will endeavour to 
explain to you. Kant said then that space must either 
be infinite or have boundary. Now you cannot conceive 
infinite space ; and you cannot conceive that there should 
be .any end to it. Here, then, are two things, one of 
which must be true, while each of them is inconceivable ; 
so that our thoughts about space are hedged in, as it 
were, by a contradiction. Again, he said that matter 
must either be infinitely divisible, or must consist of 
small particles incapable of further division. Now you 
cannot conceive a piece of matter divided into an infinite 
number of parts; while on the other hand you cannot 
conceive a piece of matter, however small, which abso¬ 
lutely cannot be divided into two pieces; for however 
great the forces are which join the parts of it together, 
you can imagine stronger forces able to tear it in pieces. 
Here again, then, are two statements, one of which must 
be true, while each of them is separately inconceivable; 
so that our thoughts about matter also are hedged in by 
a contradiction. There are several other cases of the 
same thing, but I have selected these two a 3 instructive 
examples. And the conclusion to which Ivant was led 
by the contemplation of them was, that on every side 
when we approach the limits of existence a contradiction 
must stare us in the face. The doctrine has been de¬ 
veloped and extended by the great followers of Kant; 
and this unreasonable, or unknowable, which is also 
called the absolute and the unconditioned, has been set 
forth in various ways as that which we know to be the 
true basis of all things. As I said before, I approach 
this doctrine with all the reverence which should be felt 
for that which has guided the thoughts of so many of the 
wisest of mankind. Nevertheless I shall endeavour to 
show that in these cases of supposed contradiction there 
is always something which we do not know now, but of 
which we cannot be sure that we shall be ignorant next 
year. The doctrine is an attempt to found a positive 
statement upon this ignorance, which can hardly be 
regarded as justifiable. Spinoza said, “A free man 
thinks of nothing so little as of death ; ” it seems to me 
we may parallel this maxim in the case of thought, and 
say, “ A wise man only remembers his ignorance in order 
to destroy it.” A boundary is that which divides two 
adjacent portions of space. The question, then, “ Has 
space (in general) a boundary ? ” involves a contradic¬ 
tion in terms, and is therefore unmeaning. But the 
question, “ Does space contain a finite number of cubic 
miles, or an infinite number ? ” is a perfectly intelligible 
and reasonable question, which remains to be answered 
by experiment. The surface of the sea would contain a 
finite number of square miles, if there were no land to 
bound it. Whether or no the space in which we live is 
of this nature remains to be seen. If its extent is finite, 
we may quite possibly be able to assign that extent next 
year; if, on the other hand, it has no end, it is true 
that the knowledge of that fact would be quite different 
from any knowledge we at present possess, but we have 
