Schopenhauer: the principle of sufficient reason
Schopenhauer: On the Fourfold Root of the Principle of Sufficient Reason (Über die vierfache Wurzel des Satzes vom zureichenden Grunde)
Summary
Schopenhauer's early dissertation (1813, revised 1847) examines the "principle of sufficient reason" — the insight that nothing is without a reason. He criticises the unclear use his predecessors (Wolff above all) made of this principle and sorts it systematically into four distinct roots, according to the mode of knowledge involved.
1. The general thesis
The principle of sufficient reason runs: Nothing is without a reason why it is. — But "reason" means different things depending on the kind of object presented to the subject. Schopenhauer distinguishes four kinds of reason, none of which can be reduced to another.
2. The four roots
- The reason of becoming (causality in experience)
- Concerns changes in the world of the senses.
- Every change has a cause.
- The basis of natural science: the linking of appearances in space and time.
- The reason of knowing (logical justification)
- Concerns judgements and inferences.
- A judgement is true only if it follows from other, already accepted judgements.
- Here the principle appears as the logical principle of justification.
- The reason of being (space and time)
- Space and time are a priori forms of order in which every element receives its position through the others.
- A point in space can only be determined through its relation to other points; likewise a moment through its relation to other moments.
- The reason of acting (motivation)
- Concerns the conduct of the subject as a willing being.
- Every action springs from a motive that necessarily leads to the act of will.
- This forms the basis of ethics and psychology.
3. Why the distinction matters
- The fourfold meaning prevents confusion between logical, physical, mathematical and practical justification.
- The principle is not uniform: it is formally identical while its content differs.
- Schopenhauer thereby joins Kantian epistemology (space, time and causality as forms of intuition) to a systematic analysis of the concept of justification.
4. Its further role
- The text supplies the epistemological groundwork for Schopenhauer's main work (The World as Will and Representation).
- The fourth root in particular, motivation, opens the way to his later metaphysics of the will.
The core idea: Schopenhauer breaks the principle of sufficient reason down into four irreducible types of justification — becoming, knowing, being, acting — and so gives a precise, systematic ordering of the conditions under which something "has a reason".
Wikipedia
🇬🇧 Principle of sufficient reason 🇩🇪 Satz vom zureichenden Grund — the German article the passage below is quoted from
The "principle of reason" stands as the common umbrella term, as the shared root of all the kinds of relation that appear in the represented world. Schopenhauer assigns these relations to four different classes, in each of which particular objects act on one another in a different way, so that a distinct form of the principle of reason prevails.
As the first class Schopenhauer takes the class of "intuitive, complete, empirical representations", in which the "principle of sufficient reason of becoming" prevails. Put simply, this class represents the physical level of natural science, the level at which the principle of cause and effect appears: for something to come to be, it needs a cause that acts on it.[9]
The second class, by contrast, comprises concepts, by which Schopenhauer means the products of reason, that is, language. In this class the "principle of sufficient reason of knowing" prevails. For abstract thought, which is carried out in concepts, always operates with judgements which, if they are true, express a piece of knowledge. The second class of objects thus represents the linguistic and formal level of representations, the level at which the principle of reason essentially describes the relation between premises and conclusion, or between ground of knowledge and consequence.[10]
With the third class of representations Schopenhauer identifies time and space. These are to be considered here in their purely formal shape, whereas they already occur in the first class, though there in their union as a material product (time united with space is, for Schopenhauer, the same as matter and hence as causality). Between the parts in space and in time we find the relation of position (in space) and of succession (in time). To this proportionality, which forms the basis of all being, Schopenhauer assigns the "principle of sufficient reason of being".[11]
Finally, Schopenhauer names a last class whose representations refer to a single object, namely the "subject of willing": a person regards the inner process of willing within them as something objective; they regard themselves as a willing subject. Within this object, causality once again prevails, though not an "external" causality as in the first class but an "internal" one: here the motive corresponds to the cause and the action to the effect. The principle assigned to it is the "principle of sufficient reason of acting".[12]
To each class Schopenhauer assigns a "subjective correlate"[13] through which the respective principle of reason presents itself to us: the first class exists through the understanding, the second through reason, the third through pure sensibility and the fourth through the inner sense, or self-consciousness.
Historical sources and quotations
ἀναγκαῖον πάντα τὰ γιγνόμενα διὰ τινὰ αἰτίαν γίγνεσθαι· πῶς γὰρ ἂν χωρὶς τούτων γίγνοιτο;
Translation: "It is necessary that everything which comes to be, comes to be through some cause; for how could it come to be without one?"
Source: Plato, Timaeus 28a.
πᾶν δὲ τὸ γιγνόμενον ὑπ’ αἰτίου τινὸς ἐξ ἀνάγκης γίγνεσθαι· παντὶ γὰρ ἀδύνατον χωρὶς αἰτίου γένεσιν σχεῖν.
Translation: "Everything that comes to be, comes to be of necessity through some cause; for it is impossible for anything to have a coming-to-be without a cause."
Source: Plato, Timaeus 28a (immediately following the passage quoted above).
μάλιστα μὲν καὶ πρῶτον δοκεῖε τὸ μηδὲν ἀναιτίως γίγνεσθαι, ἀλλὰ κατὰ προηγομένας αἰτίας.
Translation: "Above all and first of all it should hold that nothing comes to be without a cause, but in accordance with preceding causes."
Source: Plutarch, De fato ("On Fate"), ch. 3 (568a).
πᾶσα ἐπιστήμη διανοητική, ἢ καὶ μετέχουσα τι διανοίας, περὶ αἰτίας καὶ ἀρχὰς ἐστί.
Aristotle, Metaphysics, Book Alpha (Α, 1, 981b 5—10).
Literally translated: "Every science of thought, or even one that has some share in thought, is concerned with causes and principles."
More freely: "All science that rests on thinking — or that has any share in thinking at all — is concerned with causes and first principles."
ἐπιστάσθαι δὲ οἰόμεθα ἕκαστον ἁπλῶς, ὅταν τὴν αἰτίαν οἰώμεθα γινώσκειν, δι’ ἣν τὸ πρᾶγμά ἐστιν, ὅτι ἐκείνου αἰτία ἐστίν, καὶ μὴ ἐνδέχεσθαι τοῦτο ἄλλως εἶναι.
Translation: "We think we know a thing in the strict sense only when we believe we know the cause through which the thing is, and know that it is the cause of it, and that it cannot be otherwise."
Source: Aristotle, Analytica Posteriora (Posterior Analytics) I, 2, 71b9—12.
αἰτίαι δὲ τέσσαρες· μία μὲν τὸ τί ἦν εἶναι· μία δὲ τὸ τίνων ὄντων ἀνάγκη τοῦτο εἶναι· ἑτέρα δὲ ἡ τί πρῶτον ἐκίνησε· τετάρτη δὲ τὸ τίνος ἕνεκα.
📍 Source: Aristotle, Physics II, 3 (194b23 ff.).
Translation: "There are four causes:
- the essence, or the what-it-was-to-be (τὸ τί ἦν εἶναι = the essence / the form),
- that out of which something is, inasmuch as it is necessary that it be out of it (τὸ τίνων ὄντων ἀνάγκη τοῦτο εἶναι = the matter),
- that which first set it in motion (ἡ τί πρῶτον ἐκίνησε = the moving cause),
- that for the sake of which something is (τὸ τίνος ἕνεκα = the end)."
👉 In the usual terminology they are therefore called:
Formal cause (causa formalis)
Material cause (causa materialis)
Efficient cause (causa efficiens)
Final cause (causa finalis)
We see, then, that the ancients had not yet arrived at a clear distinction between the demand for a ground of knowledge to justify a judgement and the demand for a cause to bring about a real process. § 6, Arthur Schopenhauer: On the Fourfold Root of the Principle of Sufficient Reason