For such want to have things both ways, desiring the livingness of life without its perils, and the safety of death without its deadness, and some of us do actually get this for a considerable time, but we do not get it by plating ourselves with armour as the turtle does.  We tried this in the Middle Ages, and no longer mock ourselves with the weight of armour that our forefathers carried in battle.  Indeed the more deadly the weapons of attack become the more we go into the fight slug-wise.

Slugs have ridden their contempt for defensive armour as much to death as the turtles their pursuit of it.  They have hardly more than skin enough to hold themselves together; they court death every time they cross the road.  Yet death comes not to them more than to the turtle, whose defences are so great that there is little left inside to be defended.  Moreover, the slugs fare best in the long run, for turtles are dying out, while slugs are not, and there must be millions of slugs all the world over for every single turtle.  Of the two vanities, therefore, that of the slug seems most substantial.

In either case the creature thinks itself safe, but is sure to be found out sooner or later; nor is it easy to explain this mockery save by reflecting that everything must have its meat in due season, and that meat can only be found for such a multitude of mouths by giving everything as meat in due season to something else.  This is like the Kilkenny cats, or robbing Peter to pay Paul; but it is the way of the world, and as every animal must contribute in kind to the picnic of the universe, one does not see what better arrangement could be made than the providing each race with a hereditary fallacy, which shall in the end get it into a scrape, but which shall generally stand the wear and tear of life for some time.  “Do ut des” is the writing on all flesh to him that eats it; and no creature is dearer to itself than it is to some other that would devour it.

Nor is there any statement or proposition more invulnerable than living forms are.  Propositions prey upon and are grounded upon one another just like living forms.  They support one another as plants and animals do; they are based ultimately on credit, or faith, rather than the cash of irrefragable conviction.  The whole universe is carried on on the credit system, and if the mutual confidence on which it is based were to collapse, it must itself collapse immediately.  Just or unjust, it lives by faith; it is based on vague and impalpable opinion that by some inscrutable process passes into will and action, and is made manifest in matter and in flesh:  it is meteoric—­suspended in mid-air; it is the baseless fabric of a vision so vast, so vivid, and so gorgeous that no base can seem more broad than such stupendous baselessness, and yet any man can bring it about his ears by being over-curious; when faith fails, a system based on faith fails also.