These demands of prejudice and folly can never be satisfied; and therefore many of the imputations which learning suffers from disappointed ignorance, are without reproach. But there are some failures, to which men of study are peculiarly exposed. Every condition has its disadvantages. The circle of knowledge is too wide for the most active and diligent intellect, and while science is pursued, other accomplishments are neglected; as a small garrison must leave one part of an extensive fortress naked, when an alarm calls them to another. The learned, however, might generally support their dignity with more success, if they suffered not themselves to be misled by the desire of superfluous attainments. Raphael, in return to Adam's inquiries into the courses of the stars, and the revolutions of heaven, counsels him to withdraw his mind from idle speculations, and employ his faculties upon nearer and more interesting objects, the survey of his own life, the subjection of his passions, the knowledge of duties which must daily be performed, and the detection of dangers which must daily be incurred. This angelick counsel every man of letters should always have before him. He that devotes himself to retired study naturally sinks from omission to forgetfulness of social duties; he must be therefore sometimes awakened and recalled to the general condition of mankind. I am far from any intention to limit curiosity, or confine the labours of learning to arts of immediate and necessary use. It is only from the various essays of experimental industry, and the vague excursions of minds sent out upon discovery, that any advancement of knowledge can be expected; and, though many must be disappointed in their labours, yet they are not to be charged with having spent their time in vain; their example contributed to inspire emulation, and their miscarriages taught others the way to success. But the distant hope of being one day useful or eminent, ought not to mislead us too far from that study which is equally requisite to the great and mean, to the celebrated and obscure; the art of moderating the desires, of repressing the appetites, and of conciliating or retaining the favour of mankind. No man can imagine the course of his own life, or the conduct of the world around him, unworthy his attention; yet, among the sons of learning, many seem to have thought of every thing rather than of themselves, and to have observed every thing but what passes before their eyes: many who toil through the intricacy of complicated systems, are insuperably embarrassed with the least perplexity in common affairs; many who compare the actions, and ascertain the characters of ancient heroes, let their own days glide away without examination, and suffer vicious habits to encroach upon their minds without resistance or detection,