Occasional Harmfulness of Knowledge.—The utility involved in the unchecked investigation of knowledge is so constantly proved in a hundred different ways that one must remember to include in the bargain the subtler and rarer damage which individuals must suffer on that account. The chemist cannot avoid occasionally being poisoned or burnt at his experiments. What applies to the chemist, is true of the whole of our culture. This, it may be added, clearly shows that knowledge should provide itself with healing balsam against burns and should always have antidotes ready against poisons.