22 THE GROUNDWORK OF SCIENCE

the initiation and performance of psychical phenomena

(phenomena which constitute the data and basis of Logic)

may claim priority over, and to be more fundamental than,

Logic itself.

But the science of reasoning cannot, for another reason,

validly lay claim to be primary and fundamental, since it

requires other data than those given it by Psychology. Now

in order to prove anything by reasoning, we must show that

it necessarily follows, as a consequence, from other truths,

on the truth of which its own truth depends. Such other

truths must therefore be deemed more indispensable than

the thing they are called on to prove. Evidently we cannot

prove everything. However long may be our arguments,

we shall at last come to statements which must be taken

for granted as ultimate. One such statement is that which

affirms the validity of reasoning. If we had to prove the

validity of the reasoning process, then either we must

argue in a circle, or our process of proof must go on for

ever without ever coming to a conclusion. In other words,

there could be no such thing as proof at all. There must

then, if any human knowledge is trustworthy, be some

truths which require no proof, but are evident in and by

themselves. Once more, then, that science, whatever it may

be, which thus deals with the basis of all reasoning, and

therefore of all Psychology, of all Logic, and also of all

Mathematics, would seem to have, if anything has, a valid

claim to be the most primary and fundamental of all

sciences. But the science which does this is Metaphysics !

Metaphysics, however, though it thus deals with what is

so primary and fundamental, is a science which has also to

do with the human mind, with our views concerning an

external world, and with whatever constitutes the subject-

matter of every other science. For of what docs the

science of Metaphysics treat?

the initiation and performance of psychical phenomena

(phenomena which constitute the data and basis of Logic)

may claim priority over, and to be more fundamental than,

Logic itself.

But the science of reasoning cannot, for another reason,

validly lay claim to be primary and fundamental, since it

requires other data than those given it by Psychology. Now

in order to prove anything by reasoning, we must show that

it necessarily follows, as a consequence, from other truths,

on the truth of which its own truth depends. Such other

truths must therefore be deemed more indispensable than

the thing they are called on to prove. Evidently we cannot

prove everything. However long may be our arguments,

we shall at last come to statements which must be taken

for granted as ultimate. One such statement is that which

affirms the validity of reasoning. If we had to prove the

validity of the reasoning process, then either we must

argue in a circle, or our process of proof must go on for

ever without ever coming to a conclusion. In other words,

there could be no such thing as proof at all. There must

then, if any human knowledge is trustworthy, be some

truths which require no proof, but are evident in and by

themselves. Once more, then, that science, whatever it may

be, which thus deals with the basis of all reasoning, and

therefore of all Psychology, of all Logic, and also of all

Mathematics, would seem to have, if anything has, a valid

claim to be the most primary and fundamental of all

sciences. But the science which does this is Metaphysics !

Metaphysics, however, though it thus deals with what is

so primary and fundamental, is a science which has also to

do with the human mind, with our views concerning an

external world, and with whatever constitutes the subject-

matter of every other science. For of what docs the

science of Metaphysics treat?