THE OBJECTS OF SCIENCE 73

And, indeed, with regard to the secondary qualities of

bodies, more might yet be urged in defence of the veracity

of our faculties respecting them than we have yet advanced.

Xo one has ever shown, or can, we believe, show, that it is

impossible for our intellect to obtain, through our sensations

of colour, sound, etc., the truest notions it is possible for

us to have concerning the objective qualities which give

rise to those sensations. The objective cause, whatever

it may be, must be admitted to be occult in each case,

except as it may be made more or less known to us by

the sensations it occasions. Granting, for argument's sake,

the absolute truth of the undulatory theory of light, the

objective condition of an object which causes it to select

certain rays for reflexion must be admitted to be as yet

quite occult. Therefore, it cannot be denied that there may

be such a conformity between objective qualities and the.

effects they produce on us, that those effects may be the

best means possible for giving us the best understanding

we can attain to of what those objective qualities really are.

Though those effects may be, and probably are, far from

telling us the whole truth, though the objective qualities

that produce them may be very different from such effects,

and though much ignorance about such objective qualities

(the existence of which we do know) may thus have to be

added to our ignorance about various other qualities which

probably exist unknown to us nevertheless, our knowledge,

however fragmentary, is in part true, and, therefore, our

faculties, though inadequate to reveal to us much we might

wish to understand, are nevertheless not mendacious. But

some persons, strange to say, have affirmed that incomplete

knowledge is error; and that what we know only in part,

we therefore know wrongly.

Yet such an affirmation is surely a most irrational one.

Is the statement " the angles at the base of an isosceles

And, indeed, with regard to the secondary qualities of

bodies, more might yet be urged in defence of the veracity

of our faculties respecting them than we have yet advanced.

Xo one has ever shown, or can, we believe, show, that it is

impossible for our intellect to obtain, through our sensations

of colour, sound, etc., the truest notions it is possible for

us to have concerning the objective qualities which give

rise to those sensations. The objective cause, whatever

it may be, must be admitted to be occult in each case,

except as it may be made more or less known to us by

the sensations it occasions. Granting, for argument's sake,

the absolute truth of the undulatory theory of light, the

objective condition of an object which causes it to select

certain rays for reflexion must be admitted to be as yet

quite occult. Therefore, it cannot be denied that there may

be such a conformity between objective qualities and the.

effects they produce on us, that those effects may be the

best means possible for giving us the best understanding

we can attain to of what those objective qualities really are.

Though those effects may be, and probably are, far from

telling us the whole truth, though the objective qualities

that produce them may be very different from such effects,

and though much ignorance about such objective qualities

(the existence of which we do know) may thus have to be

added to our ignorance about various other qualities which

probably exist unknown to us nevertheless, our knowledge,

however fragmentary, is in part true, and, therefore, our

faculties, though inadequate to reveal to us much we might

wish to understand, are nevertheless not mendacious. But

some persons, strange to say, have affirmed that incomplete

knowledge is error; and that what we know only in part,

we therefore know wrongly.

Yet such an affirmation is surely a most irrational one.

Is the statement " the angles at the base of an isosceles