Pierre-Joseph Proudhon, Justice in the Revolution and in the Church, Volume I, “Program,” section II.
§ II. — The definition of philosophy.
Philosophy is composed of a certain number of questions that have been regarded at all times as the fundamental problems of the human mind, and that for that reason have been declared inaccessible to the common people. Philosophy, it was said, is the science of the universal, the science of principles, the science of causes; this is why we can speak of universal science, the science of things visible and invisible, the science of God, of man and of the world,Philosophia est scientia Dei, hominis et mundi.
We believe that the questions which philosophy occupies itself are all questions of common sense; we believe all the more that, far from constituting a universal science, these questions only deal with the very conditions of knowledge. Before we think of becoming erudite, it is necessary to begin by being philosophical. Is that so much to boast of?
Thus the first and most important question, for all of philosophy, is to know what philosophy is, what it wants, and above all what it can do. What does all this come down to? The reader will judge.
Philosophy, following the etymological signification of the word, the constant practice of thinkers, the most certain results of their labors, and the best-accredited definitions, is the Search for, and, insofar as it is possible, the Discovery of the reason of things.
It has required much time and effort by the seekers, to come to that conclusion, which it seems the first  comer would have found, if he had only followed common sense, and which everyone will definitely understand.
It follows that philosophy is not science, but the preliminary to science. Isn’t it rational to conclude, as we just did, that education, instead of ending with philosophy, must begin with it? What we call the philosophy of history, or the philosophy of the sciences, is only an ambitious way to designate science itself, that is to say, that which is most detailed, most generalized in our knowledge, scientists by profession liking to stick to the pure and simple description of facts, without seeking their reason. As the reason of things is discovered, it assumes rank in science, and the scientist follows the philosopher.
Let us examine our definition more closely.
The word thing, one of the most general in the language, must be understood here to refer, not only to external objects, in opposition to persons, but to all that which, in the man himself, both physical and moral, can furnish material for observation: sentiments and ideas, virtue and vice, beauty and ugliness, joy and suffering, speculations, errors, sympathies, antipathies, glory and decadence, misery and felicity. Every manifestation of the human subject, in a word, all that passes in his soul, his understanding and his reason, as well as in his body; everything that effects him, either as an individual or in society, or which emanates from him, becoming thus an object of philosophy, is considered, with regard to the philosopher, a thing.
By reason we mean the how and why of things, as opposed to their nature, which is impenetrable. Thus, in each thing, the philosopher will note the beginning, duration and end; the size, the shape, the weight, the composition, the constitution, the organization, the properties, the power, the faculties; the increase, the diminution, the evolutions, series, proportions, relations and transformations; the habits, variations, maxima, minima et means; the attractions, appetites, accompaniments, influences, analogies; in short all that can serve to name known the phenomenality of things  and their laws. He will abstain from all investigation, and from any conclusion, on the very nature or en soi of things, for example on matter, mind, life, force, cause, substance, space or time, considered in themselve, and setting aside their appearances or phenomena.
Thus, by its definition, philosophy declares that there is a side in things which is accessible to it, which is their reason, and another side about which it can no absolutely nothing, which is their nature: can one show at once more sincerity and more prudence? And what would be better for the people than this modesty?… Philosophy, by its own testimony, is the search for, and, if possible, the discovery of the reason on things; it is not the search for, and still less the discovery of their nature: we will not complain about this distinction. What would a nature be without a reason or appearances? And if the latter were known, who would dare to say that the former was to be missed?
To render account, in three words, of that which occurs inside, that he observes or carries out outside, of which his senses and his consciousness give testimony, and the reason of which his mind can penetrate: that, for man, is what it is to philosophize, and all that which allows itself to be grasped by the eyes and the mind is matter for philosophy. As for the intimate nature of things, that je ne sais quoi of which metaphysics cannot stop talking, and which it imagines or conceives after having set aside the phenomenality of things as well as their reason, if that residue is not a pure nothing, we don’t know what to make of it; it interests neither or sensibility nor our intelligence, and it does not even have anything in it to excite our curiosity.
Well, now. In what way is all that outside the range of the common people? Just as we are, do we not incessantly, and without knowing it, make philosophy, as the good M. Jourdain made prose? Who is the man who, in the affairs of the world, concerns himself with anything but that which interests his mind, his heart or his senses? To make ourselves consummate philosophers, it is only a question of making ourselves more sensitive to what we do, feel and say: is that so difficult? As for the contemplative, those who wanted to see beyond the reason  of things and to philosophize on their very nature, they have ended by putting themselves outside nature and reason; they are the lunatics of philosophy.
- The coming of the people to philosophy
- The definition of philosophy
- On the quality of the philosophical mind (next)
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