218 THE GROUNDWORK OF SCIENCE

scientific progress; and later on* we noted, in an introductory

manner, the absolute certainty which attends our reflex

consciousness. These remarks were necessary preliminaries

to some subsequent considerations which we then brought

forward. Now, however, the time has come for us to study

the question of certainty deliberately and as fully as we

are able, and to call the reader's attention to those con-

siderations which earlier (when speaking of reflex conscious-

ness) we said we would reserve for a future chapter.

In the first place, it is evident that we must be certain

of something, and that, do what we may, we cannot get

rid of our certainty. For if anyone were to affirm he was

certain of nothing, and that to no proposition could he

give an unhesitating and fully confident assent, he would

thereby contradict himself, for he would at the same time

be affirming the certainty of his own disbelief in and denial

of certainty.

To avoid this charge of self-contradiction he might,

perhaps, go on to say : " Oh ! I do not affirm that there

is no certainty ; I am far from denying that there may be

such a thing ; all I affirm is that I doubt everything, even

whether I have any conviction about certainty one way

or the other." But by so objecting he does not cease to

affirm certainty: all the difference is that his certainty takes

a different form from that before attributed to him.

Instead of asserting the certainty of his denial of certainty,

he would thereby be affirming the certainty that his mind

was in a state of doubt. But that is a matter about which

anyone may be as certain as of any other fact of belief or

conviction.

Concerning the present mental state in which anyone

knows himself to be whether it be a state of doubt or

belief, or a state of having a sensation of blue or of a sour

* p. 140.

scientific progress; and later on* we noted, in an introductory

manner, the absolute certainty which attends our reflex

consciousness. These remarks were necessary preliminaries

to some subsequent considerations which we then brought

forward. Now, however, the time has come for us to study

the question of certainty deliberately and as fully as we

are able, and to call the reader's attention to those con-

siderations which earlier (when speaking of reflex conscious-

ness) we said we would reserve for a future chapter.

In the first place, it is evident that we must be certain

of something, and that, do what we may, we cannot get

rid of our certainty. For if anyone were to affirm he was

certain of nothing, and that to no proposition could he

give an unhesitating and fully confident assent, he would

thereby contradict himself, for he would at the same time

be affirming the certainty of his own disbelief in and denial

of certainty.

To avoid this charge of self-contradiction he might,

perhaps, go on to say : " Oh ! I do not affirm that there

is no certainty ; I am far from denying that there may be

such a thing ; all I affirm is that I doubt everything, even

whether I have any conviction about certainty one way

or the other." But by so objecting he does not cease to

affirm certainty: all the difference is that his certainty takes

a different form from that before attributed to him.

Instead of asserting the certainty of his denial of certainty,

he would thereby be affirming the certainty that his mind

was in a state of doubt. But that is a matter about which

anyone may be as certain as of any other fact of belief or

conviction.

Concerning the present mental state in which anyone

knows himself to be whether it be a state of doubt or

belief, or a state of having a sensation of blue or of a sour

* p. 140.