Of mischievous habits which students are liable to contract, there are few against which they require a more earnest caution than that of indulging in what are popularly called “castles in the air”. This intellectual luxury assumes very various forms, according to the character or predominant passion of the individual. We need not here discuss the most detestable species of it, which consists in brooding over sinful imaginations. That of course belongs so to the threshold of Hell, that it ought to be needless to point out the ruin of the whole character, moral, intellectual, and physical, which is its unfailing consequence. But it may be well just to hint, that even where a habit of reverie does not deal with anything absolutely sinful, it is still highly dangerous in many ways to all improvement, and its disastrous effects on the mental constitution can only be compared to those of dram-drinking on that of the body. It weakens the will, enfeebles the power of application and industry, saddens the spirits, and in a word, takes away all the health and vigour of the mind. Both philosophers and saints, both men of the world and ascetical writers, all tell you the same, and speak in the very strongest terms about it. The following passage from Johnson’s Rambler is in point.

It has often been observed that the most studious are not always the most learned. There is, indeed, no great difficulty in discovering that this difference of proficiency may arise from the difference of intellectual powers, of the choice of books, or the convenience of information. But I believe it likewise frequently happens that the most recluse are not the most vigorous prosecutors of study. Many impose upon the world, and many upon themselves, by an appearance of severe and exemplary diligence, when they in reality give themselves up to the luxury of fancy, please their minds with regulating the past, or planning out the future ; place themselves at will in varied situations of happiness, and slumber away their days in voluntary visions. There is nothing more fatal to a man whose business is to think, than to have learned the art of regaling his mind with those airy gratifications. Other vices or follies are restrained by fear, reformed by admonition, or rejected by the conviction which the comparison of our conduct with that of others may in time produce. But this invisible riot of the mind, this secret prodigality of being, is secure from detection and fearless of reproach. The dreamer retires to his apartment, shuts out the cares and interruptions of mankind, and abandons himself to his own fancy; new worlds rise up before him, one image is followed by another, and a long succession of delights dances around him. He is at last called back to life by nature or by custom, and enters peevish into society, because he cannot model it to his own will. He returns from his idle excursions with the asperity, though not with the knowledge, of a student, and hastens again to the same felicity with the eagerness of a man bent upon the advancement of some favourite science. The infatuation strengthens by degrees, and, like the poison of opiates, weakens his powers without any external symptom of malignity. This captivity it is necessary for any man to break, who has any desire to be wise or useful, to pass his life with the esteem of others, or to look back with satisfaction from his old age upon his earlier years. (Johnson’s Rambler, No. 89)

So much for the merely philosophical and moral view of the habit of castle-building. It seems tolerably strong, but listen to what Dr. Faber has to say on the same subject. In his new work, just come out, Growth in Holiness, after giving some instances of castle-building, even of the seemingly harmless kind, for instance, a religious man’s spending an hour in fancies, such as giving magnificent mental alms, or imagining himself bearing crosses heroically, or founding hospitals, or entering austere orders, or arranging edifying death-beds, and the like, he says:

Do not be startled at the strong words, but this castle-building literally desolates and debauches the will. It passes over it like a ruinous eruption, leaving nothing fresh, green, or fruit-bearing behind it, but a general languor, peevishness, and weariness with God. (Growth in Holiness, by Very Rev. Dr. Faber, p. 235)

These are words that ought to sink deep into the heart of every student, because the evil against which they warn in tones so awful, is one upon which many a very promising youthful mind has made shipwreck of itself.