To what extent is solipsism a relevant philosophical theory in modern society?
I have determined it to be irrelevant in an ethical sense but not in a philosophical one.
Answer by Peter Jones
The subtleties and complexities of these issues would normally prevent me from attempting an answer but by explaining them so clearly.in his answer Dr. Klempner has made life relatively easy. I would endorse his criticisms of the various views he mentions.
While the theory of Solipsism as commonly defined and formulated is of no use to man or beast, most forms of it being blatantly absurd, the unfalsifiability of Solipsism is of vital importance in philosophy and consequently of vital importance to all of us. It means that we cannot falsify the Perennial explanation of Solipsism and of why it is unfalsifiable. This would be consistent with the truth of its explanation.
If we reject the various forms of Solipsism noted by Dr. Klempner then there is just one remaining. This would be form of Solipsism described by the Buddhist philosopher-monk Noble Nagarjuna in the second-century CE. This is both an ontological and ethical theory as for him these two areas of knowledge cannot be separated.
The idea that we cannot derive an ‘ought’ from an ‘is’ is peculiarly scholastic or ‘Western’ idea and the opposite of the truth. There would be no other way to derive an ‘ought’ except from an ‘is’ and it is as a consequence of this, as you will note from looking around you, that when we do not know what ‘is’ we are left with a choice between believing in some sort of highly judgemental monotheistic Leviathan or just doing what we feel like doing.
Nagarjuna explains ‘what is’ and in so doing explains the unfalsifiability of Solipsism. This is his famous ‘Two Truths’ doctrine, a didactic device explaining why not just Solipsism but all metaphysical questions are undecidable. It would be because the multiplicity of individual sentient beings would be contingent, not fundamental. For a fundamental analysis nothing would really exist or ever really happen. The fundamental nature of Reality would be beyond conceptualisation due to the nature of what it is. Lao Tsu tells us everything follows from what the Tao is and if Tao is fundamental then this is inevitable. The fundamental nature of Reality would be undifferentiated, the ‘Unity’ or ‘Unicity’ spoken of by the mystics. This would be all that is truly real and it is denoted in the literature as the ‘Real’.
This ‘Unity’ would encompass all of us and award us our reality as individual instances of ‘me’ and ‘my world’. There is no suggestion that nothing exists, only that contrary to our usual idea Existence is not fundamental. We tend to imagine Existence is fundamental but mysticism says it is mental and reduces to a prior state. This would be the reason why Solipsism is unfalsifiable.
At a conventional level of analysis for which ‘me’ and ‘my world’ seem to be truly real Solipsism is clearly false. If we endorse naive realism then it will appear to be absurd and its unfalsififiabilty will seem just another ‘barrier to knowledge’. For a fundamental analysis, however, Solipsism would be true. There would just one real phenomenon and it would be Me. Not just me but you and every instance of ‘me’ there could ever be.
So, on this view Solipsism would be true and false. We cannot rigorously state it is either without denying the dual-aspect nature of Reality. It would not be rigorous to say Solipsism is true or false and this would be why it is unfalsifiable. It cannot be formulated is such a way that it is true or false. Scholastic philosophers can easily formulate various versions of Solipsism and work out none of them make sense, but they cannot work out why logic and experience cannot finally falsify it. As far as we can tell from our own experience and our own logical analysis it might be true. Nagarjuna and the Perennial philosophy explain why this is. It would be because it is not exactly false.
This would be what Heidegger proposes when he explains altruistic behaviour, a phenomenon biologists are still trying to explain, as ‘the breakthrough of a metaphysical truth’. He is saying that the true nature of Reality is such that we can derive an ethical scheme from ‘what is’, and this is because at the level of what truly is ‘we’ are in fact ‘One’. It would be an intuition of our common identity, an experience of empathy with the other, that generates truly altruistic behaviour. Altruism would be motivated by an intuition that Solipsism is in some sense true. Thus when we help others we help ourselves. The distinction between selfishness and altruism breaks down.
Nagarjuna’s explanatory doctrine of ‘Two Truths’ or ‘Worlds’ explains why metaphysical problems are undecidable. It is a difficult doctrine to understand but profoundly simple in its application. When you find yourself confronted by a metaphysical dilemma such as Solipsism you just endorse Compatibilism, This is not quite what Nagarjuna suggests but it would be a first approximation and it works. All you would be doing is rejecting all the extreme theories that are known not to work. The difficulty is not applying this idea but making sense of it. It is said that it would be impossible to do this merely by thinking about it, but this is not to say there would be no point in doing so.
A general name for this view is ‘non-dualism’. It is the rejection of all extreme metaphysical views. It is the proposal that all ‘oughts’ derive from the same ‘is’ and that we are It. Reality would be ‘advaita’ or ‘not-two’. It would follow that sentient beings should be nice to each other and help each other out, just as they nice and helpful to themselves. The reason we behave differently would be that it is not an easy task to learn who we really are and thus know that Solipsism is not entirely false. A complete realisation is called ‘Enlightenment’. Philosophers everywhere at least generally agree that all other ideas are unworkable, for this is why they generally agree that metaphysical questions are undecidable.
The good news is that if Nagarjuna is right then once you begin to understand the unfalsifiability of Solipsism you will begin to understand the unfalsifiability of all such problems. Thus while his view is not easy to get to grips with you may find it considerably simplifies philosophy.