The criterion

In El criterio, a work published in 1845, Jaime Balmes offers the reader a simple, profound and complete criterion for directing human understanding to its own object, that is, to the knowledge of truth.
Balmes’ willingness to build a positive theology in dialogue with the most advanced science of his time is surprising.
The criterion is, according to its author,

“An essay for directing the faculties of the human spirit by a system different from those hitherto followed.”

It is, therefore, an original method and, in its essential lines, indispensable to learn to think well. It is a question of exercising intellectual activity, to know the truth and to direct the understanding along the path that leads to it. Balmes shows in this book an infinite faith in the methods of thought and in the ability to endow them with ethical and human truths.
In the introductory chapters (I to III), Balmes defines what the art of thinking well is, extols its transcendence and sets two conditions of it:

• The good use of care
• and the wise choice of intellectual activity, which implies the full use of native skills.

The body of the work (chapters IV to twenty-first) contains a thorough study of speculative understanding. In order to its objects — possibility, existence and nature of things — and in order to the forms of its activity, its methods and its auxiliary faculties — heart and imagination.
In chapter XXII and last, which occupies almost a third of the work, Balmes examines practical understanding. It shows how to correctly choose the objectives of our actions and the most suitable means to achieve them, without being carried away by passions.