HOW could we reply, how could our thoughts and glances penetrate the infinite and the invisible, we who neither understand nor even see the thing by which we see and which is the source of all our thoughts? In fact, as has been very justly observed, man does not see light itself. He sees only matter, or rather the small part of the great worlds which he knows by the name of matter, touched by light. He does not perceive the immense rays that cross the heavens save at the moment when they are stopped by an object of the nature of those which his eye is accustomed to see upon this earth: were it otherwise, the whole space filled with innumerable suns and boundless forces, instead of being an abyss of absolute darkness which absorbs and extinguishes the clusters of beams that shoot across it from every side, would be but a prodigious, untenable ocean of flashes. Shakespeare's famous lines:

We move in the illusion of seeing and knowing that which is strictly indispensable to our little lives. As for all the rest, which is well-nigh everything, our organs not only debar us from reaching, seeing or feeling it, but even restrain us from suspecting what it is, just as they would prevent us from understanding it, if an intelligence of a different order were to bethink itself of revealing or explaining it to us. It is impossible for us, therefore, to appreciate in any degree whatsoever, in the smallest conceivable respect, the present state of the universe and to say, as long as we are men, whether it follows a straight line or describes an nnmense circle, whether it is growing wiser or madder, whether it is advancing towards the eternity which has no end or retracing its steps towards that which had no beginning. Our sole privilege within our tiny confines is to struggle towards that which appears to us the best and to remain heroically persuaded that no part of what we do within those confines can ever be wholly lost.