Leibniz's three simple arguments that the mind must contain innate (a priori) ideas
http://www.academia.edu/915473/Leibniz_Argument_for_Innate_Ideas " THE THREE ARGUMENTS Proposition to be proven: The (human) Mind is not a Tabula Rasa [blank slate] ever. T1.1 : Because it contains principles on which necessary truths rest, and these principles did not originate outside the mind. T1.2 : Because it contains ideas of reflection, i.e it is itself the source of inner knowledge. T1.1 P1 The Mind knows both truths of matter of fact and truths of reason P2 The Mind knows truths of reason (from P1 by Simplification) P3 The truths of reason are necessary, universally valid (true in all possible words) and absolutely certain C1 Therefore the Mind knows necessary and universal truths (from P2 and P3 by Substitution) P4 Necessity, universality and certainty can either be established by means of induction from external sensory data or they may originate from the mind itself. P5 Induction is inadequate in yielding necessity, universal validity and certainty. C2 Therefore necessity, universal validity and certainty of truths of reason can be original with the mind itself. (from C1, and P4 & P5 with Disjunctive Syllogism) P6 If necessity and certainty are original with the mind, then they are contained within it. C3 Hence the mind contains these originally in itself (from P6, C2 and ModusPonens) P7 If the mind contains originally an item of knowledge, then the mind is not empty ever. C4 Therefore the mind is not empty ever. (from C3 and P7 and Modus Ponens) T1.2 P1 The mind has Ideas by means of Reflection P2 Ideas of Reflection manifest the capacity of the mind to know itself. P3 The mind can know itself inwardly either by relying on the senses for assistance or it is itself endowed with this capacity. P4 The senses can deliver knowledge (ideas) regarding only the external world. C1 Hence the mind's capacity for reflecting on itself is an endowed capacity. (from P3 and P4 and Disjunctive Syllogism) P5 If the mind possesses an endowed capacity, then it contains it in itself without having it acquired. C2 The mind contains without acquiring the reflecting capacity (from C1, P5 and Modus Ponens) P6 If a mental item is contained in the mind without being acquired, then it is innate. C3 Hence the mind's reflecting capacity is innate (from C2 and P6 and Modus Ponens) P7 If the mind has an innate item, then it cannot be empty at its inception P10 If the mind contains something innately (from its inception) then it contains it continuously. C4 Therefore the mind is not empty ever (from P7 and P10 and Hypothetical Syllogism) T2 Proposition to be proven: that the mind has the capacity of actively searching and finding innate truths within itself, not merely knowing them. In other words: The capacity to know these truths is different from the capacity the understanding has of merely being capable of coming to know (receive) them. P1 Either a mental faculty is a bare faculty or it is a predetermined, dedicated, capacity to search for specific objects in the mind P2 An epistemic faculty is a 'bare faculty' iff it is merely an indeterminate disposition to receive truths (by definition) C1 Therefore a mental faculty is either an indeterminate disposition to receive truths or a redetermined, dedicated, capacity to search for specific truths in the mind (from P1 and P2 by Substitution) P3 The epistemic capacity of knowing necessary truths is a mental faculty C2 Therefore the epistemic capacity of knowing necessary truths is either a bare faculty or a predetermined dedicated capacity to search for specific such truths (from C1 and P3 by Substitution) P4 If the epistemic capacity of knowing necessary truths is a bare faculty of receiving, then it is not the source of such truths P5 T1.1. (above) has shown that the mind is the source of the validity (proof) of necessary truths C3 Therefore the epistemic capacity of knowing necessary truths is not a bare faculty (fromP4 and P5 and Modus Tollens) C4 Therefore the epistemic capacity of knowing necessary truths is a predetermined dedicated capacity to search for specific objects (from P1 and C3 with Disjunctive Syllogism) I have also used the analogy of the veined block of marble, as opposed to an entirely homogeneous block of marble, or to a blank tablet...[I]f there were veins in the block which marked out the shape of Hercules rather than other shapes, then the block would be more determined to that shape and Hercules would be innate to it...even though labour would be required to expose the veins and to polish them to clarity, removing everything that prevents them from being seen. This is how ideas and truths are innate in us as inclinations, dispositions, tendencies, or natural potentialities and not as action; although these potentialities are always accompanied by certain actions, often insensible ones, which correspond to them.(5) [A]t every moment there is in us an infinity of perceptions unaccompanied by awareness or reflection; that is alterations in the soul itself, of which we are unaware because these impressions are either too minute and too numerous or elsetoo unvarying...But when they are combined with others they do nevertheless have their effect and make themselves felt. (6) [A] special affinity which the human mind has with [necessary truths]...is what makes us call them innate. So it is not a bare faculty...a mere possibility of understanding those truths; it is rather a disposition...a preformation which determines our souls and brings it about that they are derivable from it. (7) [A] 'consideration of the nature of things' is nothing but the knowledge of the nature of our mind and of those innate ideas, and there is no need to look for them outside oneself . (New Essays on Human Understanding, Preface and Bk. Ch.i.) " Dr. Roger B Clough NIST (ret.) [1/1/2000] See my Leibniz site at http://independent.academia.edu/RogerClough -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to firstname.lastname@example.org. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.