Sealed-envelope, cipher and combination lock tests seek to obtain evidence for post-mortem survival by having a person write a message or create an unrevealed code or lock combination while alive and transmit information about it through a medium after they die. No such test has yet been unequivocably successful.
- FWH Myers and Oliver Lodge left notes in sealed envelopes but it is not clear they were able to communicate their contents before the envelopes were opened.
- Robert H Thouless devised influential ciphers, but computers later determined their solutions without post-mortem communication, demonstrating an important vulnerability in the method.
- Ian Stevenson adapted the cipher idea to combination locks, but despite repeated attempts, no locks he or others have set have been opened.
Introduction
Sealed-envelope, cipher and combination lock tests have been proposed to test the possibility of communications from deceased persons, thereby providing experimental evidence for the survival of human consciousness after bodily death.
The logic is simple: A person writes a note and seals it in an envelope or creates a secret key (a password or lock combination) which is transmitted through a medium post-mortem. If a medium receives a communication matching the note in the envelope or provides the key to decrypting the note or opening the lock, this would provide objective evidence of survival.
Robert H Thouless, who introduced the concept of cipher tests for mediumistic communications, opined that ‘the proper reason for trying to find scientific evidence on the problem of survival lies in its importance for science, not for religion. If it is a fact that the departed survive and can communicate with us, we want to have proof of that fact because without such proof our science is incomplete’.1Thouless (1952), 19.
Sealed-Envelope Tests (1890s-1930s)
William James
In 1890, William James described a failed attempt to communicate through Leonora Piper the contents of a message written before death and left in a sealed envelope, but observed, ‘It would be hard to devise a better test than this would have been, had it immediately succeeded, for the exclusion of thought transference from living minds.’2Myers et al. (1890), 567. This, evidently, was the beginning of the sealed-envelope tests.
FWH Myers
Frederic WH Myers wrote a note in 1891 and sealed it in an envelope he left with Oliver Lodge. Following Myers’s death in 1901, Margaret Verrall took up automatic writing in an effort to provide the discarnate Myers a means to communicate and, in 1904, after a series of messages ostensibly from him, wrote something that referred explicitly to the envelope. It was then opened but Verrall’s script appeared to bear ‘no resemblance’ to Myers’s note and the test was judged a failure.3Anon. (1905). This, however, was not the end of the story. Lodge and others began to perceive connections with Myers’s then-unpublished writings that suggested to them that, in the manner of the interlocking cross-correspondences, Verrall’s script had indeed referenced Myers’s note.4Salter (1958).
Oliver Lodge
Lodge himself left a sealed envelope enclosing a note but he also was unable to communicate its contents post-mortem. Thouless reports that he was present on occasions when Lodge was communicating through mediums but Lodge seemed to dodge the opportunity to say what the note in his sealed envelope was about.5Thouless (1972), 161.
Angelos Tanagras
In 1933, Greek physician Angelos Tanagras proposed to Theodore Besterman of the Society for Psychical Research (SPR) that instead of communicating verbally through mediums, the discarnate act psychokinetically on the material environment (in the manner of a poltergeist). Tanagras left coded locations in six sealed envelopes deposited with the SPR, to be opened after his death. He died in 1971, but his strategy appears to have been no more successful than the verbal messaging.6Pallikari (2021).
Cipher Tests (1948-1987)
Robert Thouless (1948)
Thouless speculated about the difficulties a discarnate mind might face in recalling specific details, such as what was written in a note, in contrast to the atmosphere of emotionally significant events. He concluded, ‘if anything of the sealed-package type is to be attempted, it is important that the experimental material should be simple, striking, and easy to remember.’7Thouless (1972), 161.
In an attempt to redress shortcomings of the sealed-envelope tests, Thouless proposed encoded texts, the key to which would be communicated through a medium.8Thouless (1948a, 1948b). He told Arthur Berger in correspondence that he thought his cipher tests were his most significant contributions to parapsychology.9Berger (1985), 57.
Thouless initially produced two encrypted passages, employing different coding techniques, the so-called Playfair cipher10Simmons (2013). (Passage I) and a book cipher (Passage II). If a communication attempt was unsuccessful, the encryption remained intact, so that further trials were possible. This overcame a major problem with the sealed-envelope tests, which perforce concluded when the envelopes were opened.11Thouless (1948a).
Thouless became depressed after his wife died and his mind became so confused before his own impending death that he told Ian Stevenson that he did not think he would be able to carry out his programme to communicate the keys to his ciphers after his death, and indeed, no post-mortem communications have been received from him.12Stevenson et al. (1989), 335.
An anonymous cryptanalyst deciphered Passage I shortly after its publication. The key turned out to be ‘Surprise’. Thouless replaced Passage I with a third encrypted text, Passage III, using the double Playfair cipher, which utilized two keywords rather than one.13Thouless (1949b). The Passage III encryption was broken in 1995 by computer scientists James Gillogly and Larry Harnisch.14Gillogly & Harnisch (1996) For criticisms of the way Thouless constructed his cypher, see Oram (1996). The key words were ‘Black Beauty.’ Then, in 2019, Richard Bean, an IT expert at the University of Queensland, Australia, managed to have Passage II deciphered.15Bean (2019, 2020). Thus, all three of Thouless’s encrypted passages have been revealed without communications from him through mediums.
TE Wood (1950)
Thouless encouraged others to follow his lead in developing cipher tests. One who accepted his suggestion was solicitor and longtime SPR member T.E. Wood, who adopted an encryption system based on the Vigenère letter square. Wood introduced a financial incentive for attempts to break his code during his lifetime, offering to pay £20 to anyone who succeeded. Wood was born in 1887, so we may presume that he has since passed, but so far, he has not communicated the key to his cipher and there have been no reports that it has been solved by others.
Tribbe & Mulders (1980)
In 1980, Frank C Tribbe and Clarissa Mulders of the Survival Research Foundation (SRF) – which was incorporated around 1971 by Tribbe, an attorney, and the author Susy Smith – announced a ‘Volunteer Archival Drive’ to collect ciphers encoded according to Thouless’s method. These ciphers were to be held in the SRF archives and the SRF offered a $1,000 reward to any medium (or other individual) who could produce the keys and decode the ciphers within three years of the deaths of the volunteers.16Tribbe (1980). To date, there have been no reports of successful communications of keys to the ciphers preserved by the SRF.
Arthur Berger (1987)
Arthur S Berger, an American lawyer who at one time was President of the SRF, introduced his own ‘by the numbers test’ in his 1987 book Aristocracy of the Dead. Berger sought to simplify both the procedures involved in enciphering text and the keys to be communicated through mediums. He proposed selecting a word at random from a dictionary, preferably an unabridged dictionary. Every letter in this word and the definition following was numbered consecutively, then these numbers, representing letters, were used to encode a chosen passage. This passage, or rather the numbers representing it, along with a note as to the dictionary employed, were lodged with the SRF.17Berger (1987), 163-65. See also Berger (1990), 56-58; Berger & Berger (1991), 228-30. As with the Thouless ciphers, only the key words needed to be remembered and communicated post-mortem. However, as with the Thouless and other cipher tests, no successful communications have been reported.
Combination Lock Tests (1968)
Ian Stevenson (1968)
In 1968, Ian Stevenson proposed what he considered an improvement over Thouless’s cipher tests – messages in containers secured by combination locks, whose solutions were to be communicated post-mortem.18Stevenson (1968, 1976, 1997).
Stevenson derived this idea from the experience of the English sensitive Helen Greaves, whose husband kept important documents in a small box secured by a combination lock. Greaves’s husband died without telling her the combination and she made various attempts to guess it, before she felt that she received a communication from him with the correct numbers.19Greaves (1967); Stevenson (1968), 248.
Stevenson believed a combination lock would offer the same advantages over sealed envelopes as Thouless’s ciphers, yet be both easier to set up and easier to unravel later. He gave instructions on how to convert a phrase into numbers for the lock, with either the phrase or the numbers to be communicated after death.20Stevenson (1968).
Stevenson set a lock which he left with the Division of Perceptual Studies (DOPS) at the University of Virginia. He encouraged others to send him their own locks but received so many in a few months that he was forced to accept them only from the elderly or persons whose death was imminent. Stevenson died in 2007 but despite several attempts, his lock has not yet been opened; nor have any of the other locks at DOPS been opened.
Robert Thouless
In addition to his cypher tests, Thouless left a combination lock. Regarding the latter, he wrote to Stevenson in January 1970 that he had set the combination with ‘numbers corresponding to the first six letters of the two-word key to the cipher message given in my second article, using your table for changing letters to numbers.’21Stevenson et al. (1989), 331-32. Thouless died in 1984. His lock was later opened, but not in response to a communication from him.22Stevenson (1996).
JG Pratt
Another person who set a combination lock was the parapsychologist JG Pratt, who, ‘being a highly numerate person’, chose to begin with random numbers, then ‘obtained from them the corresponding letters (using the published code) and devised a mnemonic, using these letters as the initial ones of a six-word phrase’.23Stevenson et al. (1989), 331. Pratt
attached more importance to his numbers than to his mnemonic and, aware that he might forget the numbers, he several times practiced opening his lock (when alone in a closed room). On one occasion, before and after an illness, he thought that he had forgotten his mnemonic, but afterward found that he had not.24Stevenson et al. (1989, 331), citing Stevenson (1976, 226-27).
Pratt died suddenly in November 1979 while visiting a neighbour in Charlottesville, Virginia. After his death, Stevenson received purported communications with numbers from numerous people, but none proved correct. Stevenson also visited mediums in London during 1981 and 1982, but although he carried Pratt’s lock in his pocket at the time, nothing relating to it or to Pratt’s mnemonic was communicated.25Stevenson et al. (1989), 331.
Where Things Stand in 2026
The use of sealed envelopes, ciphers and combination locks as evidentiary tests of post-mortem survival has so far proven of little consequence. Nonetheless, the potential of these methods still intrigues the public. The SPR is contacted not only in the context of the renewed study of bygone attempts, but also with offers to accept new combination locks with claims to have secret methods for communicating from beyond the grave.26Private and confidential contact with the SPR archive officer.
The matter appears more complicated from the research point of view. Even if discarnate communicators had succeeded in conveying the information they hoped to, it is by no means clear that this would have provided the survival evidence they wished. W. Peter Mulacz has pointed out that although cipher and combination lock tests are fundamentally different in the ESP required to unravel them, both are vulnerable to psi. The cipher solutions could in principle be acquired telepathically from the writers while they were living as well as by a medium after his death, whereas the combination locks, which were mechanical, could theoretically be accessed clairvoyantly. For this reason, Mulacz considered combination locks to be weaker potential tests than ciphers.27Mulacz (1997). See also Johnson (1984, 247-48) on this point.
It is not that post-mortem communication with the living through mediums or in other ways – for instance, dreams and apparitions – is inconceivable. The psychical research literature abounds in examples, as Martin Johnson pointed out in the SPR’s Journal.28Johnson (1983, 1984). The challenge for researchers is how best to arrange for prospective tests, rather than waiting for communications to be reported. This may begin with thinking through what it must be like for a discarnate consciousness to function and designing tests with that in mind.
As Johnson noted,29Johnson (1984), 248. a discarnate agent might influence the living and the material environment in many ways, not simply by relaying keys to solving a cipher or opening a combination lock, and it may be that by expanding the range of communication channels we expect, we can achieve greater success with prospective tests. Johnson made a proposal in line with WG Roll’s ‘psi field’,30Roll (1957–64, 1982). which presumes consciousness to have a field effect before and after death, but so far, there are no reports of Johnson’s test being attempted and its potential superiority to the other approaches is an open question.
Additional Reading
The following items, not included under Works Cited, are provided for interested readers who wish to study the topic further.
Anon. (1975). Letter to the Editor [regarding the Thouless cipher test]. Journal of the Society for Psychical Research 48, 184-5.
Anon. (1985–86). Has Dr Thouless survived death? Journal of the Society for Psychical Research 53, 135-36.
Berger, A.S. (1984). Experiments with false keys. Journal of the American Society for Psychical Research 78, 41-54.
Berger, A.S. (1984). The development and replication of tests for survival. Parapsychological Journal of South Africa 5, 24-35.
Thouless, R.H. (1963). The cipher test of survival. Theta 2 (July), 1-3.
Thouless, R.H. (1975). Letter to the Editor. Journal of the Society for Psychical Research 48, 185.
Thouless, R.H. (1984). Do we survive bodily death? Proceedings of the Society for Psychical Research 57, 213, 1-52.
Archival Resources
Robert Thouless Survival Test: Papers and Correspondence, 1948 – 1986. University of Cambridge.
Melvyn Willin and James G Matlock
Works Cited
Anon. (1905). Opening of an envelope containing a posthumous note left by Mr. Myers. Journal of the Society for Psychical Research 12, 11-13.
Bean, R. (2019). Cryptology from the crypt: How I cracked a 70‑year‑old coded message from beyond the grave. [Full text.] The Conversation.
Bean, R. (2020). Letter to the Editor (regarding Thouless 1948a). [Full text.] Journal of the Society for Psychical Research 84/1, 56-57.
Berger, A.S. (1985). In Memory of Robert H. Thouless. Journal of the Society for Psychical Research 53, 56-60.
Berger, A.S. (1987). Aristocracy of the Dead: New Findings in Postmortem Survival. Jefferson, North Carolina, USA: McFarland & Company.
Berger, A S. (1990). Tests for communication with the dead. In What Survives? Contemporary Explorations of Life after Death, ed. by G. Doore, 51–60. Tarcher.
Berger, A.S., & Berger, J. (1991). Reincarnation: Fact or Fable? Wellingborough, Northants, UK: Aquarian Press.
Gillogly, J.L., & Harnisch, L. (1996). Cryptograms from the crypt. Cryptologia 20/4, 325-29.
Greaves, H. (1967). The Dissolving Veil. London: Churches Fellowship for Psychical and Spiritual Studies.
Johnson, M. (1983). A technique for testing of the psi-field theory with some implications for survival research. Part I. Journal of the Society for Psychical Research 51, 795, 177-88.
Johnson, M. (1984). A technique for testing of the psi-field theory with some implications for survival research. Part II. The survival issue. Journal of the Society for Psychical Research 52, 796, 245-52.
Mulacz, W.P. (1997). Can combination lock tests provide any proof of survival? Journal of the Society for Psychical Research 61, 846, 330-33.
Myers, F.W.H., Lodge, O.J., Leaf, W., & James, W. (1890). A record of observations of certain phenomena of trance. Proceedings of the Society for Psychical Research 6(17), 436-659.
Oram, A.T. (1996). The original Thouless two-word code. Journal of the Society for Psychical Research 61, 116-19.
Pallikari, F. (2021). Angelos Tanagras: An experiment to test survival. [Full text.] Journal of Anomalistics 21, 223-42.
Roll, W.G. (1957–64). The psi field. In Proceedings of the Parapsychological Association, Vol. 1, ed. By W.G. Roll & J.G. Pratt, 32-65. Durham, North Carolina, USA: Parapsychological Association.
Roll, W.G. (1982). The changing perspective on life after death. In Advances in Parapsychological Research 3, ed. S. Krippner, 147-291. New York: Plenum Press.
Salter, W.F. (1958). F.W.H. Myers’ posthumous message. Proceedings of the Society for Psychical Research 52, 1-32.
Simmons, G.J. (2013). Playfair cipher. [Full text.] Encyclopedia Britannica.
Stevenson, I. (1968). The combination lock test for survival. [Full text.] Journal of the American Society for Psychical Research 62, 246-54.
Stevenson, I. (1976). Further observations on the combination lock test for survival. Journal of the American Society for Psychical Research 70, 219-29.
Stevenson, I. (1996). The opening of Robert Thouless’ combination lock. Journal of the Society for Psychical Research 61, 843, 114-115.
Stevenson, I. (1997). Letter to the Editor. Journal of the Society for Psychical Research 62, 848, 92-93.
Stevenson, I., Oram, A.T., & Markwick, B. (1989). Two tests of survival after death:
Report on negative results. Journal of the Society for Psychical Research 55, 329-36.
Thouless, R.H. (1948a). A test of survival. Proceedings of the Society for Psychical Research 48, 175, 253-63.
Thouless, R.H. (1948b). Additional note on a test of survival. Proceedings of the Society for Psychical Research 48, 176, 342-43.
Thouless, R.H. (1952). Psychical Research Past and Present. London: Society for Psychical Research.
Thouless, R.H. (1972). From Anecdote to Experiment in Psychical Research. London: Routledge and Kegan Paul
Tribbe, F.C. (1980). The Tribbe/Mulders code. Journal of Religion and Psychical Research 3, 44.
Wood, T.E. (1950). A further test for survival. Proceedings of the Society for Psychical Research 49, 105-6.