This is a two volume set, this is volume 1. This work prepared by Cardinal Mercier and and the Professors of the Higher Institutes of Philosophy at Louvain prior to World War I is just as valuable today, when truth is attacked from all quarters, including the philosophical. Volume 1 contains Cosmology, Psychology, Epistemology, Criteriology, General Metaphysics and Ontology Volume 2 contains Natural Theology, Logic, Ethics and a History of Philosophy This work begins: "General View of Philosophy at the Present Day.-Has philosophy the right to be named among human sciences? What is its legitimate place among them? According to one opinion which is seldom expressly formulated but which we may say is none the less 'in the air', the special sciences have nowadays monopolized everything that can be the object of such knowledge as is certain and can be subjected to verification. In proportion as our instruments of observation have become more perfect, the number of special sciences has increased; and as each special science maps out for itself a definite field of research, it would seem that there is no room for any science other than the positive sciences. If then philosophy has a claim to exist, it can only be as a science outside positive science, busying itself with shadowy speculations and contenting itself with fictions for its conclusions or, at least, with conjectures that cannot be verified. "Such an opinion arises from a failure to understand the role philosophy thinks it right to assume and, in consequence, the scope of its claims. Philosophy does not profess to be a particularized science, with a place alongside other such sciences and a restricted domain of its own for investigation; it comes after the particular sciences and ranks above them, dealing in an ultimate fashion with their respective objects, inquiring into their connexions and the relations of these connexions, until finally it arrives at notions so simple that they defy analysis and so general that there is no limit to their application. So understood, philosophy will exist as long as there are men endowed with the ability and energy to push the inquiry of reason to its furthest limit. So understood, it is a living fact, and it has a history of more than two thousand years."
Mercier’s manual is a great overview for anyone with an intermediate level understanding of thomism, like myself. I describe it as an “intermediate” text, but this is only in comparison to the thomistic tradition. Even an intermediate thomist text is more sophisticated than 99% of contemporary philosophy. It displays all of the characteristic virtues and shortcomings of that era of thomism. On the one hand, it is clear, well-organized, and thorough. Mercier’s thought is always precise and takes full advantage of the developments of the thomist tradition. On the other hand, sometimes Mercier is more Suarezian or Kantian than I would like (though his Kantian tendencies are sometimes a positive).