what is not, and never can be, known.

CONTENTS.

PART I.

THE PHYSICAL BASIS.

LETTER PAGE
I. To a young man of letters who worked excessively 17

II. To the same 22

III. To a student in uncertain health 27

IV. To a muscular Christian 42

V. To a student who neglected bodily exercise 47

VI. To an author in mortal disease 53

VII. To a young man of brilliant ability, who had just taken his
degree 57

PART II.

THE MORAL BASIS.

I. To a moralist who had said that there was a want of moral
fibre in the intellectual, especially in poets and artists 67

II. To an undisciplined writer 80

III. To a friend who suggested the speculation "which of the moral
virtues was most essential to the intellectual life" 91

IV. To a moralist who said that intellectual culture was not
conducive to sexual morality 98

PART III.

OF EDUCATION.

I. To a friend who recommended the author to learn this thing
and that 104

II. To a friend who studied many things 110

III. To the same 120

IV. To a student of literature 130

V. To a country gentleman who regretted that his son had the
tendencies of a dilettant 134

VI. To the principal of a French college 137

VII. To the same 143

VIII. To a student of modern languages 149

IX. To the same 153

X. To a student who lamented his defective memory 165

XI. To a master of arts who said that a certain distinguished
painter was half-educated 170

PART IV.

THE POWER OF TIME.

I. To a man of leisure who complained of want of time 176

II. To a