THE METHODS OF SCIENCE 107

(3) We can know not only our actions, sensations, imagi-

nations, reminiscences, perceptions, conceptions, and

inferences, but also our own substantial and con-

tinuous personal existence.

(4) We know that if certain premisses be true, then

whatever logically follows from them must be true

likewise.

(5) Since we thus know certain truths indirectly by infer-

ence, we must also know some things directly and

see that they are self-evident.

(6) Nothing can at the same time both be and not be.

(7) Some axioms are self-evident.

(8) Every change and every new existence must be due to

some cause.

(9) Nature is uniform.

(10) Some things are necessary and others are contingent

The fact that the above ten propositions are true and

certain is then implied by the methods of science.

Unless we are convinced, and act on the conviction,

that the propositions thus implied are true, science is

logically impossible, and any scientific man who should

deny any one of them would either deceive himself or

try to deceive other people. Without their acceptance it

is impossible to have any consistent, harmonious, and

stable system of ordered knowledge any true science.

More than that, if these ten propositions were really doubted

by anyone, he would thereby necessarily fall into a state

of mental paralysis and intellectual inanition, in all that

relates to scientific knowledge.

Having thus recognized these important convictions,

which find a necessary place amongst the implications

(3) We can know not only our actions, sensations, imagi-

nations, reminiscences, perceptions, conceptions, and

inferences, but also our own substantial and con-

tinuous personal existence.

(4) We know that if certain premisses be true, then

whatever logically follows from them must be true

likewise.

(5) Since we thus know certain truths indirectly by infer-

ence, we must also know some things directly and

see that they are self-evident.

(6) Nothing can at the same time both be and not be.

(7) Some axioms are self-evident.

(8) Every change and every new existence must be due to

some cause.

(9) Nature is uniform.

(10) Some things are necessary and others are contingent

The fact that the above ten propositions are true and

certain is then implied by the methods of science.

Unless we are convinced, and act on the conviction,

that the propositions thus implied are true, science is

logically impossible, and any scientific man who should

deny any one of them would either deceive himself or

try to deceive other people. Without their acceptance it

is impossible to have any consistent, harmonious, and

stable system of ordered knowledge any true science.

More than that, if these ten propositions were really doubted

by anyone, he would thereby necessarily fall into a state

of mental paralysis and intellectual inanition, in all that

relates to scientific knowledge.

Having thus recognized these important convictions,

which find a necessary place amongst the implications