Category: edmund gurney

Exploring Phantasms of the Living (1886) through Machine…

Exploring Phantasms of the Living (1886) through Machine Learning: Topic Discovery with Latent Dirichlet Allocation

NOTE: Click to open graphics for an expanded and clearer view of the findings they contain  

Phantasms of the Living, published in 1886 by the Society for Psychical Research (SPR), was a landmark study that presented the case for “telepathy” or thought transference from mind to mind.  The study consisted of 702 cases spanning over 1400 pages that considered several varieties of spontaneous telepathic experiences collectively referred to “phantasms of the living”  

  • The case collection examined non-sensory and internalized impressions, many of which were presentiment experiences involving dreams, clairvoyance, visions, feelings or an awareness in connection with the deaths of family members or friends.  These experiences often coincided with the approximate time of death
  • Cases also considered

    sensory and externalized impressions, in particular apparitional representations of living persons, who were perceived to be in moments of crisis or danger.  These situations appeared evidential of shock-induced forms of thought transference from a distressed agent to a percipient in the form of telepathic hallucinations

As a follow-on to the earlier wordcloud project, we wondered whether unsupervised machine learning could discover main topics within Phantasms of the Living.  For the project, two varieties of generative topic models were used: Latent Dirichlet Allocation (LDA) and probabilistic Latent Semantic Analysis (pLSA)

Both models view documents as having a latent semantic structure of topics that can be inferred from co-occurrences of words in documents. The mathematics underlying both models are beyond the scope of this post, but on an intuitive level there are key differences between the two methods

  • pLSA views topics over probability distributions over words. Each word is generated by a single topic. Topics are seen as conditionally independent across the documents that produced them.  Non-Negative Matrix Factorization (NMF) is a method for finding topic clusters used for pLSA
  • LDA by contrast views documents as probability distributions over topics and topics as probability distributions over words.  All documents share the same collection of topics, but each document contains those topics in different proportions 

The project used various packages and libraries for natural language processing within the Python programming platform to include: the Natural Language ToolKit (NLTK) for processing the data set; Sci-Kit Learn to prepare and fit the LDA and NMF models; pyLDAVis was used to display the results and t-Distributed Stochastic Neighbor Embedding (t-SNE) to map topic distances

The end-to-end project pipeline involved: data set processing; conversion of words and documents into matrix and vector space; fitting the LDA and NMF models; and then displaying the results

Processing. The book was decomposed into several documents from its constituent sections, chapters and volumes for the data set. Stopwords were removed such as common prepositions and conjunctions using the wordcloud application   

  • Since telepathic experiences are spontaneous and can occur at any time or place, words conveying times and locations were removed as well as ordinal and cardinal types of rankings
  • Nouns or titles representing persons were removed (e.g. man, woman, Mr., Mrs., etc.); however, interpersonal relationships were preserved (i.e. family, friends, acquaintances or strangers)  

Conversion. Vector transformations converted the data set into a document-term matrix for mathematical processing  

  • The rows of the matrix correspond to documents with columns corresponding to the frequency of a term.  Count vectorizers count word frequencies.  Term Frequency-Inverse Document Frequency (TF-IDF) vectorizers normalize (divide) word counts by their frequency in the documents 
  • Both vectorizers converted words to lower case and removed non-word expressions. The vectorizers were also instructed to look for bigrams (or words that were often used together) such as “thought-transference” and “telepathic hallucination”

Model Fit/Display. The LDA and NMF models were fitted using ten topics.  Words within topics were sorted and ranked with respect to their frequency in and relevance within a topic

  • The LDA model was fitted with using Count and TF-IDF vectorization and ran with a maximum of 10 iterations.  LDA model results were displayed using pyLDAVis and t-SNE to map topic distances
  • The NMF model was fitted with TF-IDF vectorization only and ran with a maximum of 200 iterations. NMF model results were displayed via spreadsheet

In unsupervised machine learning data is unlabeled, hence the topics produced from both models were also unlabeled.  However words within topics often can be woven into a coherent theme

The first two pyLDAvis graphs provide the top 30 words and bigrams in Topics 1 and 2 using Count vectorization  

  • Words in Topic 1 include: “dreams”; “visions”; “impressions”; and “experiences” in connection with the “death”(s) of family members and friends.  This can be considered a “presentiment” topic.  This topic contained 67% of the top terms.  This mirrors results from the prior wordcloud project  
  • Words and bigrams in Topic 2 include: “thought-transference”, “hallucination(s)”, “phantasms”, “mind(s)”, “percipients”, “agent” and “telepathy.”  This can be considered a “crisis apparitions” topic.  This topic contained 27% of the top terms 

The third pyLDAvis graph provides the top 30 words in Topic 1 using TF-IDF vectorization

  • Topic 1 combines all the aforementioned words into one topic.  This can be considered a “presentiment and crisis apparitions” topic.  

    This topic contained 95% of the top terms, rendering all other topics comparatively insignificant in generating the documents

The spreadsheets compare LDA and NMF model runs using TF-IDF vectorizations, however, with results limited to the 10 top words.  Although topic weights and distances are not available, some topics appear more meaningful and cohesive, and are likely more impactful than others

  • There is considerable overlap between topics 6 and 7 in the LDA model and together they form the presentiment and crisis apparitions topic. Topics 0 and 1 in the NMF model respectively appear to correspond to presentiment and crisis apparitions topics
  • The bigram “thought-transference” arises in both the LDA and NMF results and is associated with the “Society” for “Psychical” Research and the late F.W.H. “Myers” who invented the term “telepathy”

This project had an extended preparation and production pipeline.  However, results clearly show that unsupervised machine learning using LDA and NMF effectively and comprehensively summarized topical content in Phantasms of the Living.  Moreover, the topics approximately corresponded to the types of internalized and externalized telepathic experiences described in the book  

This project demonstrates the usefulness of topic generation models for finding meaningful patterns in masses of unlabeled or unstructured data.  Moreover, visualization and graphing tools are essential for fully comprehending these patterns. Elsewhere in parapsychology LDA or NMF could also be applied to survey data, case collections, web or social media content of interest.  


Anaya, L. A. Comparing Latent Dirichlet Allocation and Latent Semantic Analysis as Classifiers. University of North Texas, 2011.

Blei, D. M., Ng, A. Y., & Jordan, M. I. (2003). Latent dirichlet allocation. Journal of machine Learning research, 3(Jan), 993-1022.

Christou, D. (2016). Feature extraction using Latent Dirichlet Allocation and Neural Networks: A case study on movie synopses. arXiv preprint arXiv:1604.01272.

Deerwester, S. (1988). Improving information retrieval with latent semantic indexing.

Gurney, E., Myers, F. W., & Podmore, F. (1886). Phantasms of the Living (2 vols.). London: Trübner.  Reprinted at the Esalen Center.

Pedregosa, F., Varoquaux, G., Gramfort, A., Michel, V., Thirion, B., Grisel, O., … & Vanderplas, J. (2011). Scikit-learn: Machine learning in Python. Journal of machine learning research, 12(Oct), 2825-2830.

Sievert, C., & Shirley, K. (2014). LDAvis: A method for visualizing and interpreting topics. In Proceedings of the workshop on interactive language learning, visualization, and interfaces (pp. 63-70).


pyLDAvis Graph of Topic 1 (Count Vectorization) from Phantasms of the Living Corpus. (2018, Mar 24). © Maryland Paranormal Research ®.  All rights reserved.

pyLDAvis Graph of Topic 2 (Count Vectorization) from Phantasms of the Living Corpus. (2018, Mar 24). © Maryland Paranormal Research ®.  All rights reserved.

pyLDAvis Graph of Topic 1 (TF-IDF Vectorization) from Phantasms of the Living Corpus. (2018, Mar 24). © Maryland Paranormal Research ®.  All rights reserved.

Top Words List: Latent Dirichlet Allocation (TF-IDF Vectorization) from Phantasms of the Living Corpus. (2018, Mar 24). © Maryland Paranormal Research ®.  All rights reserved.

Top Words List: Non-Negative Matrix Factorization (Frobenius) from Phantasms of the Living Corpus. (2018, Mar 24). © Maryland Paranormal Research ®.  All rights reserved.

Presentiment and Crisis Apparitions in Victorian-era Case…

Presentiment and Crisis Apparitions in Victorian-era Case Collections:  Phantasms of the Living (1886) as seen through Natural Language Processing

Presentiment in the classical sense is a form of precognition involving a feeling,  perception or premonition that something will or is about to happen.  From experimental parapsychology, the term now refers to an effect involving capacities to feel or intuit the future.  This modern sense of presentiment (feeling) sets it apart from precognition (knowing)

Phantasms of the Living, published in 1886 by the Society for Psychical Research (SPR), contains a collection of 702 Victorian-era cases involving classical presentiment phenomena occurring in various forms to include: dreams and premonitions; clairvoyance; as well as crisis apparitional experiences   

Phantasms was also a pathfinding study on extrasensory perception as it introduced the term “telepathy.”  The authors believed presentiment involving living persons in moments of crisis or danger, to include crisis apparitions, were evidence of “shock-induced” forms of thought transference

As a project, we wondered how might how machine learning might make sense of classical presentiment experiences in the Phantasms case collection  

Natural Language Processing (NLP) is a field of computing that enables computers to analyze, understand and communicate human language.  

The Natural Language Toolkit (NLTK) is a platform of libraries and programs for natural language processing written in the Python programming language

Word clouds are the most basic and familiar NLP products.  Word clouds do not support fine grained analysis, but instead provide a visualization of key words and phrases,

where the sizing of words reflects their prominence within the text

Phantasms is available in various Internet archives in a variety of digital formats. For this project, a corpus (body) of plain text was created from a reprint of Phantasms hosted at the Esalen Center 

  • To derive meaningful insights the corpus was processed to remove stop words, such as commonly used prepositions.  Since the work represents a case collection, the set of stop words was expanded to remove references to “case(s)” and “fact(s)” and how they were documented, (i.e.words like “said ” and “told”).  Formal salutations (“Mr”, “Mrs”, “Miss) were also added to stop words
  • Since presentiment experiences can occur at any time, words having a temporal character were excluded from consideration to include: “day”, “night”, “morning”, “evening”, “hour”, and “time.”  Many presentiment experiences were singular events, hence ordinal and cardinal numeric references were also removed to include: “first”, “second” as well as “one” and “two”
  • Finally, some words often associated with precognition such as “will” and “may” were also added to set of stop words to allow greater emphasis on the features of presentiment experiences

The resulting word cloud presents a case pattern of presentiment experiences involving families and friends.  Mothers featured prominently in case accounts often as the percipient, and in other instances as the agent (or source) of the presentiment experience  

Many presentiment experiences were in the form of dreams or premonitions that were coincident with the death of loved ones. However the case collection also included other forms extrasensory perception (e.g. telepathy, clairvoyance and precognition) as well as crisis apparitional experiences 

The fact that mothers featured so prominently in these presentiment cases suggests a wider question, which arises elsewhere in parapsychology, of whether there is a natural (in the sense of evolutionary) explanation for presentiment phenomena and for psi functioning writ large. Toward this end, one of the authors of Phantasms concludes:

“If the natural system includes telepathy, Nature has certainly not exhausted herself in our few hundreds of instances: that these facts should be genuine would be almost inconceivable if she had not plenty more like them in reserve”


Bem, D. J. (2011). Feeling the future: experimental evidence for anomalous retroactive influences on cognition and affect. Journal of personality and social psychology, 100(3), 407.  Hosted on Semantic Scholar

Bird, S., Klein, E., & Loper, E. (2009). Natural language processing with Python: analyzing text with the natural language toolkit. “ O’Reilly Media, Inc.”.

Gurney, E., Myers, F. W. H., & Podmore, F. (1886). Phantasms of the living (Vols. 1-2). London: Trübner & Co. Reprint by the Esalen Center, Carmel CA

Radin, D. (2016). Presentiment. Psi Encyclopedia, Society for Psychical Research


Wordcloud from Phantasms of the Living Corpus. (2018, Feb 24). © Maryland Paranormal Research ®.  All rights reserved.