The chief of the essays comprised in this volume is an "historical and critical sketch of successive philosophical conceptions respecting the relations between inductive and deductive thought." It was awarded the Heslop Gold Medal as the best dissertation by a student of Mason College, Birmingham (England), in 1887, and Miss Naden was also rewarded for it by being made an Associate of the College, an honor she well deserved. The dissertation displays a wide knowledge of scientific facts with a rare capacity for dealing with them in a philosophical spirit, and a power of acute reasoning such as few other women have ever possessed. Whether her opinions are always correct is another question. It is a profound remark that we are obliged to regard nature as a system, "because we can consider its multiplicity only in relation to one thinking subject." But we must challenge her statement that we have no certainty for assuming that the laws of nature will always remain unchanged. A change in the laws of nature would be the replacing of it by a different nature of which man could not take cognisance, and which therefore we cannot reasonably conceive to be possible. There might be a change of conditions which would introduce other laws, but these must be in conformity with, and not in opposition to, the present laws of nature, as otherwise they could not exist for us, seeing that "experience is possible in virtue of the original constitution of the mind," and therefore, according to the views of which Miss Naden is an exponent, they could not exist at all.