Kurt Gödel (1906-1978) was a powerful logician whose contributions to logic, mathematics, and philosophy were immense. He was deeply interested in those aspects of philosophy that touched on religion and one of those was his ontological proof for God’s existence.

The argument is in a line of development that goes back to Anselm of Canterbury (1033–1109). St. Anselm’s ontological argument, in its most succinct form, is as follows: “God, by definition, is that for which no greater can be conceived. God exists in the understanding. If God exists in the understanding, we could imagine Him to be greater by existing in reality. Therefore, God must exist.” A more elaborate version was given by Gottfried Leibniz (1646–1716); this is the version that Gödel studied and attempted to clarify with his ontological argument.
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Gödel is not known to have told anyone about his work on the proof until 1970, when he thought he was dying. In February, he allowed Dana Scott to copy out a version of the proof, which circulated privately. In August 1970, Gödel told Oskar Morgenstern that he was “satisfied” with the proof, but Morgenstern recorded in his diary entry for 29 August 1970, that Gödel would not publish because he was afraid that others might think “that he actually believes in God, whereas he is only engaged in a logical investigation (that is, in showing that such a proof with classical assumptions (completeness, etc.) correspondingly axiomatized, is possible).”[2] Gödel died January 14, 1978. Another version, slightly different from Scott’s, was found in his papers. It was finally published, together with Scott’s version, in 1987.

(For more see Oppy, Graham. 2017. “Ontological Arguments.” The Stanford Encyclopedia of Philosophy, (Summer 2017 Edition), edited by Edward N. Zalta.)

I find such ontological proofs, which seem to me to consist purely of semantic sophistry, unpersuasive. Apart from anything else, I have summarized in my book The Great Paradox of Science the arguments that proving the existence of any (electron, neutrino, God) purely by logic is not possible. Apologists argue that God is not like any other physical entity and thus those arguments do not apply, which strikes me as special pleading, essentially saying that they have created a unique category for God to which normal arguments do not apply. Furthermore, the possible existence of God has been hotly debated for millennia and if an existence proof had been conclusively established, then surely that would be huge news, even more so than the proof of Fermat’s Last Theorem, and everyone would be believers. The fact that this is not the case would seem to imply that these proofs are not really ‘proofs’ (which imply certainty, at least if the axioms and logic used are valid) but like the word entity, are used to mean something else that is not clearly specified.

Gödel did not come right out and say that he believed in God’s existence but asserted that he was merely engaged in a logical investigation. He did not publish this work, fearing that others might think that he actually believed in God’s existence. But his notes on the topic circulated among a few people privately and were published only after his death in 1978.

But I digress. The main purpose of this post is to highlight that he did believe in the afterlife. He did not publish his thoughts on this either but revealed them in four long letters that he wrote to his mother Marianne in 1961. His mother was not a churchgoer and had raised Gödel and his brother as freethinkers. But two days after his death, his wife told an interlocutor that “although he did not go to church, was religious and read the Bible in bed every Sunday morning.” Unfortunately, Gödel’s mother’s replies to him have not survived but, from what Gödel says in his letters, suggest that she was not entirely convinced.

His rationale for belief in an afterlife is this:

If the world is rationally organised and has meaning, then it must be the case. For what sort of a meaning would it have to bring about a being (the human being) with such a wide field of possibilities for personal development and relationships to others, only then to let him achieve not even 1/1,000th of it?

He deepens the rhetorical question at the end with the metaphor of someone who lays the foundation for a house only to walk away from the project and let it waste away. Gödel thinks such waste is impossible since the world, he insists, gives us good reason to consider it to be shot through with order and meaning. Hence, a human being who can achieve only partial fulfilment in a lifetime must seek rational validation for this deficiency in a future world, one in which our potential manifests.

Before moving on, it is good to pause and capture Gödel’s argument in a nutshell. Assuming that the world is rationally organised, human life – as embedded in the world – ought to possess the same rational structure. We have grounds for assuming that the world is rationally organised. Yet human life is irrationally structured. It is constituted by a great potential but it never fully expresses this potential in a lifetime. Hence, each of us must realise our full potential in a future world. Reason demands it.

He believed that the afterlife did not occur in this world (i.e., we are not reincarnated) but in a distinct future world.

We do not know if he persuaded his skeptical mother since we do not have her replies to him but his letters suggest that she was, to say the least, puzzled by his views.

Gödel’s was not himself Jewish but he associated closely with the Jewish intellectuals of pre-war Vienna and this was sufficient for him to be thought of as either Jewish or a friend of Jews and thus prevented him from getting academic employment and he left Vienna for Princeton in 1939 where he worked at the Institute for Advanced Studies there. He had a close friendship with Albert Einstein who deeply respected him,and who reportedly said that after he (Einstein) stopped doing any real research, he would still go to the IAS so that he coulld have the pleasure of walking home with Gödel.

Gödel’s last years were tragic.

Later in his life, Gödel suffered periods of mental instability and illness. Following the assassination of his close friend Moritz Schlick, Gödel developed an obsessive fear of being poisoned, and would eat only food prepared by his wife Adele. Adele was hospitalized beginning in late 1977, and in her absence Gödel refused to eat; he weighed 29 kilograms (65 lb) when he died of “malnutrition and inanition caused by personality disturbance” in Princeton Hospital on January 14, 1978.

Gödel was a strange and fascinating man. It would have been delightful to listen in on the conversations between him and Einstein on their walks. Free from the tight constraints of academic publishing, their powerful minds could wander freely, examining the big questions that all of us struggle with.