Many people recognize these famous lines: “I doubt therefore I think; I think therefore I am”, yet few know who spoke them and what they mean. Unfortunately, written reflections on existence since the time of Descartes have been scant, except of course those coming from these prominent philosophers : Spinoza, Locke, Hume, Malthus, Kant, Marx, Engels, Nietzsche etc. whom in their brilliance developed intricate metaphysical systems that attempted to explain the very nature of physical reality. Descartes, despite his incessant attempts at ontologicaly demonstrating the existence of God, in his view merely a prime mover and not necessarily a dogmatic Christian God, does in fact make an essential point about how ‘doubt’ is necessarily the precursor to thought, and thus the instigator of existence.
The first principle in Principia Philosophiae deals with just that, doubt. Descartes suggests that: “Veritatem inquirenti, semel in vita de omnibus, quantum fieri potest, esse dubitandum.” or that ‘it is neccessary to doubt all things, in particular those things to which we ascribe even the slightest uncertainty’. To prevent the Principia from falling into complete relativism this first principle is watered down by a third more practical principle: “Hanc interim dubitationem ad usum vita non esse referendam.” or ‘that the principle of complete doubt shouldn’t be adopted for the conduct of daily life’. Descartes suggests that this first principle should be reserved only for the contemplation of truth in philosophy and not for those mundane tasks and decisions that frequently present themselves throughout our lives. Also, in his fourth principle, and the one I think is most important, since it deals with our ability and necessity of doubting perceptible things, Descartes makes the following very important point: “Cur possimus dubitare de rebus sensibilibus” or that ‘it is possible for us to doubt perceptible things’.
Still on this fourth principle, it is necessary to mention David Hume. One of my favorite philosophers, Hume, suggested that when faced with an apparent miracle, an individual must necessarily ask himself the following question: Which is more probable? that the laws of physics and order of the universe have been suspended, in this case in my favor, or that I’m under a misaprehension. Both Hume’s and Descartes’ ontology deal with the falability of our human senses and that even first hand experiencial accounts of physical events are inherently unreliable. Descartes makes this point with undeniable clarity:”Nunc itaq; cum tantum veritati quarende incumbamus, dubitatimus imprimis, an ullae res sensibilies aut imaginabiles existant: Primo, quia deprehendimus interdum sensus errare, ac prudentie eft nunqua nimis fidere iss, qui nos vel femel deceperunt: Deinde, quia quotidie infomnis innumera videmur fentire aut imaginari, quae nusquam sunt; nullaque sic dubitanti signa apparent, quibus fomnum a vigilia certo dignofcat.” This translates into: ‘The quest for thruth must begin by first doubting the existence of those things perceptible and those belonging to the imagination. This is because we understand that our senses, more often than not, deceive us, and thus we shouldn’t place too much trust in things that have ever deceived us even once. And also that in our dreams we can conceive an infinite number of things which are nonexistent elsewhere. Thus, to a man that doubts, there seem to be no definitive distinguishing proprieties between dreams in a state of sleep and thoughts in a state of awakeness.’
Finally, Descartes’ sixth, seventh and ninth principles in his Principia Philosophiae refer to: free will, the undoubtability of doubt and the nature of thought. He has the following to say about free will: “Nos habere liberum arbirium, ad cohibendum assensum in dubis sique ad errorem vitandum.” or that ‘individuals have the free will to distinguish between doubt and certainty and thus, through logic, choose to dissent in doubtful matters, and thus avoid error.’ This point, Descartes says, can even be applied to the existence of God. Or that perhaps free will, in deciding things that may be certain or uncertain, is independent of God. And thus since the existence of God is an uncertainty, it too must be doubted. Now, on the undoubtability of doubt Descartes says that: “No posse a nobis dubitari, quin existamus dum dubitamus: adque hoc esse primum, quod ordinae philosophando cognoscimus.” or that ‘it is impossible to doubt the fact that when we are doubting, we exist; and that this is the necessary first axiom to assume in any philosophy.’ This second most important point can be rephrased, in my opinion, in the following manner: That if we do not doubt and exercise this doubt in our thoughts, we aren’t necessarily thinking; and if we are not thinking, then we are not necessarily consciouss; and if we are not consciouss we most likely do not exist, or at least we are not aware of our existence. In his ninth point Descartes discusses that thoughts, since we can articulate them and can thus confirm that they exist, must therefore imply the existence of consciousness, and therefore the existence of a mind to house this consciousness.
In conclusion, it is imporant to restate some of the Descartes’ principles in one continuous thought: ‘It is necessary to doubt all things uncertain insofar as we do not apply this principle in everyday mundane life. That our senses are falable and thus our accounts of experience can be equally erroneous. Thus our senses must be doubted as well. That free will, and thus free will to doubt things uncertain, must necessarily be independent of God for God is uncertain himself. That doubting in itself is the first necessary axiom to all philosophy and thus to existence. And finally that consciousness is demonstrated by the existence of thoughts and thus the mind.’ These principles, I think, are simple to understand, and do not require additional reading into the Principia Philosophiae. They can independently exist of the rest of Descartes’ work and still be sensible and true. I, as a materialist and positivist, agree with most of Descartes assertions and axioms in the Principia, except those infering the existence of God, and some of the points about physical experience being falable. Otherwise, my own personal contemplations about existence are very similar to Descartes’.
