not without reluctance, that the great authority of Plato can be pleaded for this low view of its functions.  In the “Laws” he enjoins a due measure thereof, but for the sake of health alone, and adds, that the sleeper is, for the time, of no more value than the dead.  Clearly, mankind would sustain some loss of good sense, were all the dullards and fat-wits taken away; and Sancho Panza, with his hearty, “Blessings on the man that invented sleep!” here ekes out the scant wisdom of sages.  The talking world, however, of our day takes part with the Athenian against the Manchegan philosopher, and, while admitting the present necessity of sleep, does not rejoice in its original invention.  If, accordingly, in a computation of the length of man’s life, the hours passed in slumber are carefully deducted, and considered as forming no part of available time, not even the medical men dispute the justice of such procedure.  They have but this to say:—­“The stream of life is not strong enough to keep the mill of action always going; we must therefore periodically shut down the gate and allow the waters to accumulate; and he ever loses more than he gains who attempts any avoidance of this natural necessity.”

As medical men, they are not required, perhaps, to say more; and we will be grateful to them for faithfully urging this,—­especially when we consider, that, under the sage arrangements now existing, all that the physician does for the general promotion of health is done in defiance of his own interests.  We, however, have further questions to ask.  Why is not the life-stream more affluent?  Sleep is needful,—­but wherefore?  The physician vindicates the sleeper; but the philosopher must vindicate Nature.

It is surely one step toward an elucidation of this matter to observe that the necessity here accused is not one arbitrarily laid upon us by Nature, but one existing in Nature herself, and appertaining to the very conception of existence.  The elucidation, however, need not pause at this point.  The assumption that sleep is a piece of waste, as being a mere restorative for the body, and not a service or furtherance to the mind,—­this must be called in question and examined closely; for it is precisely in this assumption, as I deem, that the popular judgment goes astray. Is sleep any such arrest and detention of the mind?  That it is a shutting of those outward gates by which impressions flow in upon the soul is sufficiently obvious; but who can assure us that it is equally a closing of those inward and skyward gates through which come the reinforcements of faculty, the strength that masters and uses impression?  I persuade myself, on the contrary, that it is what Homer called it, divine,—­able, indeed, to bring the blessing of a god; and that hours lawfully passed under the pressure of its heavenly palms are fruitful, not merely negatively, but positively, not only as recruiting exhausted powers, and enabling us to be awake again, but by direct contribution to the resources of the soul and the uses of life; that, in fine, one awakes farther on in life, as well as farther on in time, than he was at falling asleep.  This deeper function of the night, what is it?