264 THE GROUNDWORK OF SCIENCE

Our mere observations of natural laws can never suffice to

enable us to affirm that never and nowhere is there a

lawless condition of things, or that such a lawless condition

may not one day come within our own sphere of experience

utter irregularity of co-existences and sequences. But

here that necessary and self-evident principle the law of

causation comes in, ' and supplies us with the basis for

science which is so imperatively required. For, since there

can be no change without a cause, it follows there can be no

difference between the results of two perfectly similar sets

of antecedent conditions, and that the more completely two

sets of conditions are alike, the more completely similar will

be the results produced by them.

Thus the uniformity of nature is a necessary result of the

law of causation, which necessary and self-evident truth

gives the efficient and necessary support to that expectation

which good sense and human testimony combine to produce

in us.

But there must also be a certain proportion between any

physical or mental cause and its effects ; and our reason

assures us that we can to a considerable extent judge as

to causes by the effects they have produced. We can often

form a rational judgment as to the adequacy of some cause

to produce a given effect. No child with a toy hammer

could level the great pyramid of Egypt, and no ignorant

peasant could translate and adequately comment upon

Plato's symposium. No creature devoid of intellect could

ever perform a truly virtuous action, for it could have no

perception about ethical relations. That a cause must be

adequate in order that a given effect may be produced, is

an absolute, universal, and necessary truth, no less than is

the law of causation itself, as is commonly if tacitly assumed.*

But, as we before observed, an objection is often raised

* See ante, p. 66.

Our mere observations of natural laws can never suffice to

enable us to affirm that never and nowhere is there a

lawless condition of things, or that such a lawless condition

may not one day come within our own sphere of experience

utter irregularity of co-existences and sequences. But

here that necessary and self-evident principle the law of

causation comes in, ' and supplies us with the basis for

science which is so imperatively required. For, since there

can be no change without a cause, it follows there can be no

difference between the results of two perfectly similar sets

of antecedent conditions, and that the more completely two

sets of conditions are alike, the more completely similar will

be the results produced by them.

Thus the uniformity of nature is a necessary result of the

law of causation, which necessary and self-evident truth

gives the efficient and necessary support to that expectation

which good sense and human testimony combine to produce

in us.

But there must also be a certain proportion between any

physical or mental cause and its effects ; and our reason

assures us that we can to a considerable extent judge as

to causes by the effects they have produced. We can often

form a rational judgment as to the adequacy of some cause

to produce a given effect. No child with a toy hammer

could level the great pyramid of Egypt, and no ignorant

peasant could translate and adequately comment upon

Plato's symposium. No creature devoid of intellect could

ever perform a truly virtuous action, for it could have no

perception about ethical relations. That a cause must be

adequate in order that a given effect may be produced, is

an absolute, universal, and necessary truth, no less than is

the law of causation itself, as is commonly if tacitly assumed.*

But, as we before observed, an objection is often raised

* See ante, p. 66.