18 
and the same beings which I call myself . Here is an intuitive 
judgment involving the simple idea of personal identity.”* 
The question which first arises here is as to the simplicity of 
the idea. Is it impossible to analyze the idea of personal 
identity? Let us try both from the particulars of which it is 
a generalization, and from it, as a generalized thought, to 
these same particulars. Is the “ me ” possible as an idea 
without the (C not me ” ? Then, is either the one or the other 
possible, apart from a vast number of perceptions that must 
all be in the soul as thoughts before the thoughts of objects, 
such as the “ me” and those which are not me” can arise. 
Again, is not the thought of “ myself ” resolvable into at 
least the thought of a person, and those other thoughts which 
fix that of a person to me, so that it makes me known to 
myself as myself and not another ? 
Then as to the necessity of the idea of personal identity. 
Certain memories and reasonings make it impossible for me to 
discredit the fact that I got my dinner yesterday, so are 
certain memories and reasonings necessary to my belief that I 
am myself, and not another person. It seems, therefore, 
absurd to call certain ideas “innate,” or “ intuitive,” or 
“ necessary,” when all are equally so, if the proper occasions 
are presented. The plain state of the case is merely this — a 
truth cannot be both known and unknown in the same mind 
and at the same time. Take the ideas of my personal identity 
and that of my having had my dinner yesterday. What does 
it really amount to that these ideas will inevitably and infallibly 
spring up in my mind whenever the required conditions are 
- present ? Simply this — that when these truths are known, 
they cannot be unknown. Mr. Stewart quotes Locke as 
affirming exactly what he himself means, when the former 
says , — “ He that hath the idea of an intelligent but frail and 
weak being, made by and depending on another, who is 
omnipotent, perfectly wise and good, will as certainly know 
that man is to honour, Tear, and obey God, as that the sun 
shines when he sees it.” f What is this but that he knows 
the sun shines when he knows that it does, and so he knows 
that God is to be worshipped and obeyed when he knows that 
too ? Locke confirms this when he says , — u But yet these 
truths being never so certain, he may be ignorant of either or 
all of them who will never take the pains to employ his 
faculties as he should do to inform himself about them.” 
That is, if he is ignorant he is ignorant, and if he knows he 
* Philosophical Essays, by Dugald Stewart, ed. 1816, p. 98. 
t Locke’s Essay, book iv. chap. xiii. § 3. 
