IXTELLECTUAL ANTECEDENTS OF SCIENCE 243

They must be true objectively as well as subjectively, and

must be laws of " things " no less than laws of " thought."

They must be seen to be necessarily true everywhere and

everywhen, quite independently of any or of every mind.

If such be the case, the same laws must apply to the most

common circumstances of every-day life as well as to the

highest matters of philosophy. They must also be no mere

blind mental processes, the result of any faculty such as

instinct, or be due to any kind of non-rational impulse.

Their influence must be seen in daily life, in actions

resulting from definite and certain intellectual first principles

and necessary and evident truths, to which the competent

philosopher can always trace them. This does not mean

they are evident as such principles and truths to the mind of

every man who uses them, but that their truth is completely

evident without reflexion. In vain will the village grocer

try to persuade the farmer's wife that if from sixteen ounces

of tea two ounces be removed the rest is none the less equal

to a pound. She will be quite sure such is not the case,

though she may be quite guiltless of the knowledge of a

single axiom. Similarly, if a labourer has given the whole

of his week's wages to his wife, he will be quite sure no

part of them is still in his pocket, though he never heard

a word about any first principles. The intellectual light of

such first principles illuminates the intellect of every sane

man, be he civilized or savage. Not, most certainly, that

savages and ignorant men can know such principles as

abstract truths. But those principles, none the less, reveal

themselves to the mind in the concrete facts of every-day

life as practical motives for judging and acting. It is true

we cannot explain how these truths became thus practically

apprehended in the objects and actions of our constant

experience, but we are and must be ignorant of "how"

anything, which is for us ultimate, is whatever it may be.

244 THE GROUNDWORK OF SCIENCE

The "that" must ever be final. The "how" can never be

so, for the answer to every " how " must be a " that."

The first and most important of these principles is the

perception of the reality of existence that what we perceive

to exist evidently does in truth so exist. This is often

expressed by the formula, " A is A," a formula which to some

persons appears utterly trivial, but which, nevertheless, lies at

the basis of all our knowledge, and is a fundamental certainty

without which no science could even begin to be.

Another principle is that known as " the excluded middle,"

which affirms that any given thing must either be or not be,

closely allied with which is that great regulative principle to

which we have already adverted,* and which is called " the

principle of contradiction" the principle, namely, that nothing

can, at one and the same time, both be and not be.

Now it has been strangely objected against this law of the

universe, that it is but a law of grammar, or, at most, of logic.

It has been saidf to be but "a verbal convention," not

possessing "objective validity."

But the objector might be (as, in fact, he was) asked

"whether, if he had lost an eye, he would still remain, after

that loss, in the very same condition as he was in before ? "

If anyone does not see the objective impossibility of such

a thing in all places and at all times i.e., if he does not

apprehend the application of the law of contradiction then

he either does not understand the question, or his mental

condition is pathological.

Men may pretend to doubt such principles, their own exist-

ence, or the objectivity of mathematical truths. But their

practice demonstrates their unfailing confidence in them on

each occasion as it arises as when cheated by false accounts,

personally injured, or busied with some serious investigation.

* See ante, p. 105.

t See Nature hi Dec. loth, 1891, and Feb. nth, 1892.

They must be true objectively as well as subjectively, and

must be laws of " things " no less than laws of " thought."

They must be seen to be necessarily true everywhere and

everywhen, quite independently of any or of every mind.

If such be the case, the same laws must apply to the most

common circumstances of every-day life as well as to the

highest matters of philosophy. They must also be no mere

blind mental processes, the result of any faculty such as

instinct, or be due to any kind of non-rational impulse.

Their influence must be seen in daily life, in actions

resulting from definite and certain intellectual first principles

and necessary and evident truths, to which the competent

philosopher can always trace them. This does not mean

they are evident as such principles and truths to the mind of

every man who uses them, but that their truth is completely

evident without reflexion. In vain will the village grocer

try to persuade the farmer's wife that if from sixteen ounces

of tea two ounces be removed the rest is none the less equal

to a pound. She will be quite sure such is not the case,

though she may be quite guiltless of the knowledge of a

single axiom. Similarly, if a labourer has given the whole

of his week's wages to his wife, he will be quite sure no

part of them is still in his pocket, though he never heard

a word about any first principles. The intellectual light of

such first principles illuminates the intellect of every sane

man, be he civilized or savage. Not, most certainly, that

savages and ignorant men can know such principles as

abstract truths. But those principles, none the less, reveal

themselves to the mind in the concrete facts of every-day

life as practical motives for judging and acting. It is true

we cannot explain how these truths became thus practically

apprehended in the objects and actions of our constant

experience, but we are and must be ignorant of "how"

anything, which is for us ultimate, is whatever it may be.

244 THE GROUNDWORK OF SCIENCE

The "that" must ever be final. The "how" can never be

so, for the answer to every " how " must be a " that."

The first and most important of these principles is the

perception of the reality of existence that what we perceive

to exist evidently does in truth so exist. This is often

expressed by the formula, " A is A," a formula which to some

persons appears utterly trivial, but which, nevertheless, lies at

the basis of all our knowledge, and is a fundamental certainty

without which no science could even begin to be.

Another principle is that known as " the excluded middle,"

which affirms that any given thing must either be or not be,

closely allied with which is that great regulative principle to

which we have already adverted,* and which is called " the

principle of contradiction" the principle, namely, that nothing

can, at one and the same time, both be and not be.

Now it has been strangely objected against this law of the

universe, that it is but a law of grammar, or, at most, of logic.

It has been saidf to be but "a verbal convention," not

possessing "objective validity."

But the objector might be (as, in fact, he was) asked

"whether, if he had lost an eye, he would still remain, after

that loss, in the very same condition as he was in before ? "

If anyone does not see the objective impossibility of such

a thing in all places and at all times i.e., if he does not

apprehend the application of the law of contradiction then

he either does not understand the question, or his mental

condition is pathological.

Men may pretend to doubt such principles, their own exist-

ence, or the objectivity of mathematical truths. But their

practice demonstrates their unfailing confidence in them on

each occasion as it arises as when cheated by false accounts,

personally injured, or busied with some serious investigation.

* See ante, p. 105.

t See Nature hi Dec. loth, 1891, and Feb. nth, 1892.