You do not settle whether an argument is justified by merely showing that it is of some use. The distinction is not between useful and useless experiments but between barbarous and civilized behaviour. Vivisection is a social evil because if it advances human knowledge, it does so at the expense of human character.
It is a noteworthy fact that kicking and beating have played so considerable a part in the habits which necessity has imposed on mankind in past ages that the only way of preventing civilized men from beating and kicking their wives is to organize games in which they can kick and beat balls.
The sex relation is not a personal relation. It can be irresistibly desired and rapturously consummated between persons who could not endure one another for a day in any other relation.
The more reasonable a student was in mathematics, the more unreasonable she was in the affairs of real life, concerning which fewtrustworthy postulates have yet been ascertained.