THE scope of the following lecture is strictly limited by its title. No attempt is made to establish the truth of Christianity or Theism, but only to examine the assumption that -- as their nomenclature would imply -- "Freethought" must be synonymous with intellectual liberty, and "Rationalism" with sound reasoning. Those who start with this assumption as a first principle naturally refuse all consideration to systems of belief which they consider to be self-condemned as mere mental bondage, and, accordingly, before anything more positive can be effected, it is necessary that the ground should be cleared of fundamental misconceptions, and the foundations determined upon which valid argument must be based. It is as a contribution towards such an object that the lecture is designed.