— 59 —
Implicitly known before proposing, signifies that the Mind is capable of understanding them, or else signifies nothing.       §22. If it be said, The Understanding hath an implicit Knowledge
— 60 —
of these Principles, but not an explicit, before this first hearing, (as
they must, who will say, That they are in the Understanding before
they are known) it will be hard to conceive what is meant by a
Principle imprinted on the Understanding Implicitly; unless it be
this, That the Mind is capable of understanding and assenting firmly
to such Propositions. And thus all Mathematical Demonstrations,
as well as first Principles, must be received as native Impressions on
the Mind: which, I fear they will scarce allow them to be, who find
it harder to demonstrate a Proposition, than assent to it, when
demonstrated. And few Mathematicians will be forward to believe,
That all the Diagrams they have drawn, were but Copies of those
innate Characters, which Nature had ingraven upon their Minds.
Locke Hum I, 2, §22, pp. 59-60