PHILO 
In the firft place, the whole of the mathematics is re¬ 
duced to an empirical fcience ; that is, one derived from 
experience. Confequently it lofes all its apodi&ical cer¬ 
tainty, and the power of forcing convidlion ; for the high- 
eft argument that can be obtained from experience is the 
greateft degree of probability. But what can be more ab- 
i'urd than to fay, of the 47th problem of the firft Book of 
Euclid, that it is “highly probable” that the fquare that 
fubtends the right angle is equal to the fquares that con¬ 
tain it! The geometrician will never allow this to be 
merely probable : he w ill maintain that he has completely 
demonftrated the faft, that his proof is necejfary and uni- 
verfal, and that whoever denies it muft havelome defebt in 
his intellect. Now what follows from this? Firft, that Geo¬ 
metry is not a fcience derived from experience, becaufeit 
poffeffes necejfity and univerfality , two properties of know¬ 
ledge that do not belong to experience. Secondly, that 
■without Time and Space there can be no fcience of geo¬ 
metry whatever. Thirdly, that, unlefs Time and Space 
are properties of the Mind, geometry cannot be a pure fci¬ 
ence, that is, one not derived from experience, but which 
exifts wholly in the Mind. What indeed are the geome¬ 
trician’s point and line but purely mental things, no where 
to be found in experience. 
In the fecond place, fo far from gaining any advantage 
•with refpeft to the certainty of our knowledge from an in¬ 
dependent fpace, the very oppofite effeft is produced, 
namely,the total deftruition of all knowledge. For we have 
juft proved that the whole of our knowledge is contained in 
Time and Space , and that this faid knowledge is alfo in the 
mind ; therefore, by deprivingthe mind of that which con¬ 
tains knowledge, we annihilate knowledge itfelf. Where 
can be the difficulty of admitting that the figures in which 
external objefts are clothed are not inherent in thofe objefts, 
but are really properties of our mode of perceiving them ? 
While the fame external exiftences conftantly produce the 
fame impreflio-ns, what more do we require to guide us 
through life ? It is the very effence and nature of our Sen- 
fitive Faculty to imprefs upon every object that affefts us 
both Extension and Succession. Nothing, there¬ 
fore, can enter Space without partaking of its properties, 
that is, having its parts one near and without another, and 
being fimultaneous; and nothing can exift in Time with¬ 
out being fucceffive. The fenfations received by the hand 
or the eye do -not conftitute knowledge, until they are 
modified by the Underftanding; that is, connefted into a 
unity by being arranged under the twelve Categories. So 
that the matter of all knowledge is Senfation received in 
Time and Space ; and Its form is nothing but the Cate¬ 
gories. The adoption therefore of a Space independent 
of the Mind is one of the greateft evils that can befal fci¬ 
ence, and ftiuts the door for ever upon the Philojophy of 
Mind. It is difficult to know upon what principle we 
can afiume an external and independent Space that is to 
contain the obje£ls of our knowledge, and that this 
knowledge is not influenced by the medium by which it 
is obtained. Therefore, view the fubjeift in whatever 
light we will, ftill the dogma of independent Space is the 
moft ruinous and abfurd prejudice that infatuated com¬ 
mon fenfe can poffibly cling to. 
It would not be more ablurd to deny to our Earth its 
diurnal and orbicular motions, becaufe appearances con- 
tradidl them, than to deny that Time and Space are pro¬ 
perties of the'Mind, becaufe appearances contradift this 
opinion. In the former cafe, aftronomical fcience has put, 
the matter in fo clear a light, and repeated examinations 
of the faft have fo eftablilhed its certainty, that the posi¬ 
tions are in no danger of refutation. In the latter cafe, 
the fcience that affects that Time and Space are properties 
of the Mind, that is, modes or forms in which it receives 
the fenfations impreffed on it, is new, and therefore muft 
expeft to meet with numerous opponents. This was the 
cafe with aftronoiny. But that thefte opponents fliould 
everbeableto adduce any arguments that will fupport 
their oppofition, is as little to be dreaded, as that Eu- 
SOPHY. Ill 
clid’s axioms and definitions, which have already flood 
their ground for 2000 years, fliould be difearded for want 
of truth and confiftency. We may therefore conclude 
with perfect fafety, that the principles of Tranfcendental 
Philojophy will, together with the elements of Geometry, 
endure to the end of time. 
Can any thing be more touching than to know that we 
live in a world whofe various objedls are prefented to us 
under an immenfe variety of beautiful and harmonious 
pictures ; and that all we are at prefent permitted to 
know is, that it exifts, and that we exift in it! Is there no¬ 
thing fublime in this awful obfeurity which every-where 
furrounds us ! If the improvements in the fcience of 
Aftronomy tend to enlarge our views of the Deity, how 
much more will the eilablilhment of a perfect Philofophy 
of Mind effefl with regard to this moft definable objeft! 
for by this Philofophy the mind of man is not only fully 
laid.open to view, but the abode of the foul, and a future 
life, are rendered as comprehenfible as any mathematical 
demonftration. We may novv indeed exclaim, without 
the fear of refutation, that Man does not exist in 
Time and Space ! From this modern difeovery follows 
the moft glorious refult: that the Freedom of the 
human Will is established for ever ! For, as 
the effence or foul of man does not exift in Time and 
Space, his Will cannot be influenced by the laws which 
reflde no-where elfe, among which is Caufe and Effect, 
together with all the other Categories. All this is 
fully proved and firmly eftablilhed in the “Critic of 
Practical Reason,” (fee vol. xv. p. 767.) upon 
which bafts is ere£ted a complete and permanent Science 
of Morals. 
On lubmitting my firft article to the public through 
the medium of this Encyclopaedia, (Article Kant, vol. xi. 
p. 606.) I expreffed the high fentiments of refpedt I en¬ 
tertained for a fellow-labourer in the lludy of the human 
mind. Indeed to all the enquiries I had been able to 
make at that period, (ten years fince,) as to who was the 
firft Metaphyfician in my own country, the anfwer con¬ 
ftantly returned was, that the author of the “ Elements of 
the human Mind,” Profeffor Stewart, of the Univerfity of 
Edinburgh, held that diftinguiftied rank. To this elegant 
and accomplifned fcholar I therefore addrefied myfelfin 
all the fimplicity of truth and fincerity, in order to fubm't 
my labours to the toft of his criticifm, hoping that the 
caufe of Truth, which I had efpoufed from the bottom 
of ray heart, would be thereby benefited. In purfuance 
of this plan, I caufed my firft Effiy on Philofophy to be 
interleaved, to receive fuch remarks as might occur to him 
on any erroneous arguments I might have employed in 
fupport of my favorite dodlrine, or on any errors in the 
fubjedl itfelf. I felt confident that the foie objedt of 
every found philofopher was the eftabliffiment of Truth 
upon an immutable bafts; and that whoever exerted 
himfelf to promote this end would be favourably liftened 
to by the labourers in the fame vineyard. With this 
view I forwarded my firft attempt to this celebrated phi¬ 
lofopher; but, to my furprife, found, though he expreffed 
himfelf with the greateft politenefs, that he had neither 
time nor opportunity to enter into my lpeculations, as 
his own literary purl'uits occupied his whole time. My 
treatife was therefore returned to me without perufal ; 
and the caufe of truth gained nothing by this effort. 
In noway diftieartened by the failure of obtaining from 
this great Icholar the approval or difapproval of the prin¬ 
ciples. I was endeavouring to expound for the benefit of 
mankind ; four years afterwards I forwarded another 
treatife to Mr. Stewart, in the hope that circumftances 
might have been fo changed as to allow him forne leifure, 
at this diftant period, ro enter a little into lpeculations 
which feemed to be in perfedl harmony with thofe in 
which he had been engaged nearly the whole of hisffife. 
This writer had publiffied.a “ Philofophy of the Human 
Mind,” with which he did not feel himfelf completely 
fatisfied ; for, in the advertifement to his “ Philosophi¬ 
cal 
