ABSTRACT
The main question before us is how atheism can be compatible or consistent with accepting any form of the principle of sufficient reason (PSR). This issue concerns Schopenhauer because he is a historical example of an atheist who accepted PSR, and even wrote a treatise in defence of his interpretation of PSR. 1 Questions can be raised whether Schopenhauer correctly understood PSR. Schopenhauer’s interpretation will be confronted with Heidegger’s interpretation of PSR, and the argument will be made that Heidegger’s interpretation is superior. PSR is usually and disproportionately associated with Leibniz (even though it was first clearly formulated by his disciple Wolff), but it can be traced much further back: it occurs embryonically in Plato’s Timaeus 28a and Phaedo 99b, but more substantially and coherently in Aristotle’s Posterior Analytics 71b8-12 and following Aristotle, in Aquinas’s Summa Contra Gentiles 15. 2
Principle of sufficient reason is the English translation of the German ‘Satz vom Zurreichende Grunde’ or the Latin ‘principium sufficientis rationes’. Basically, this principle suggests that nothing is without reason ( nihil est sine ratione ). The translation is troublesome, however. The Latin ‘ratio’ and the English ‘reason’ can each be translated into either the German Grund or the German Vernunft . ‘Ratio’, as Aquinas uses it, and as Leibniz and Wolff use it whenever they refer to principium rationis sufficientis , would properly translate the Greek logos , not arche or aition . The meaning of logos is Grund as reason in the sense of foundation, basis, cause, or ground, not Vernunft, which is reason in the sense of intellect, intelligence, or judgment. As will be discussed in more detail below, for Heidegger PSR says nothing about reason but has ‘beings’ ( Seiende ) and their ground as subject matter. For Heidegger, PSR then says something about the ontology of their ‘ontic-ness’. The word ‘reason’ suggests design or intention; the word ‘ground’ is neutral on this point. Accordingly, in English, it may be more precise to speak of ‘The Principle of Sufficient Ground’—but tradition
is against us. In Latin, ratio is ambiguous; in German, Grund is not. It may help, whenever one sees the abbreviation ‘PSR’, to think of principium sufficientis rationis rather than principle of sufficient reason.
