590 PROFESSOR ALISON’S DEFENCE 
animals, and resume their office as manures, afford a manifest presumption that 
such modification takes place. 
The chief consideration which seems to have prevented Dr Dauspeny from 
acknowledging that the power which he himself supposes to exist in living beings, 
and to regulate chemical changes there, is deserving of a separate name and a 
separate inquiry, is thus stated:—“ If it is asserted that this power is to be 
directly ascribed to the vital principle itself, we pause for further information.” 
Here it seems to me manifest, that there is a misapprehension as to the correct 
meaning of words, and one which may be traced in many other speculations in 
the elementary departments of physiology,—investing the term Vital Principle 
with a meaning much more mysterious and formidable than is needful. Accord- 
ing to the only idea which I can form of what is properly termed the vital prin- 
ciple, Dr DauBeny has already admitted, in the words above quoted from him, 
that, so far as we can yet see, we must regard the vital principle as concerned in 
forming the “ wonderful products of organic life;’” because he says, that these 
result from a power residing in living matter, producing physical effects, yet 
distinct in its effects from ordinary chemical and physical forces. 
The only correct way of defining what we call Vitality, or the vital principle. 
as I have always maintained, and as I think the best authorities now admit, is 
this:—First, we describe what we call living beings. They are those, as Cuvier 
states, which originate by a process of generation, which we can describe,—are 
maintained by a process of growth and nutrition, which we can describe,—and ter- 
minate by death and decomposition, which we can describe. Then, having thus dis- 
criminated those bodies which we call living, we say that, in so far as we can satisfy 
ourselves, that any part of the phenomena which they present are inexplicable by, 
and inconsistent with, the laws regulating the changes of any other matter, we call 
them effects of the vital principle, or vitality ; and that is our definition of those 
terms. Those who object to the use of the substantive noun Vitality, or the 
Vital Principle, as a general expression for such phenomena, constantly use the 
adjective Vital, or Living, which conveys the very same meaning, and can be 
defined, as I apprehend, in no other way. The real efficient cause of these, as of 
all other phenomena in nature, is the Divine Will, and is inscrutable; but we 
know, that in all departments of Nature, this all-powerful cause acts according 
to laws which we can understand, and the discovery and application of which is 
the object of all science. When we see that any phenomena in nature take 
place according to the same law as others more familiar, we are said to explain 
them, or to assign their physical cause; but until that is clearly ascertained, we 
obey the dictates of science in declining to arrange them along with those de- 
pending on any law otherwise known to us, and endeavouring to apply the me- 
thod of induction to themselves,—and to any such isolated phenomena as may 

