The Mysticism Scale: Research Form D

Abstract

The Mysticism Scale: Research Form D (commonly known as the M Scale or Hood's Mysticism Scale) is a premier 32-item psychometric instrument developed by Ralph W. Hood, Jr. in 1975. Designed to assess subjective reports of mystical experiences, the scale translates the philosophical criteria of mystical states formulated by Walter Terence Stace (1960) into an empirically testable operational framework. The instrument systematically evaluates eight phenomenological dimensions: ego quality, unifying quality, inner subjective quality, temporal/spatial quality, noetic quality, ineffability, positive affect, and religious quality. Administered via a 5-point Likert-type scale ranging from -2 ("definitely not true") to +2 ("definitely true") with a designated undecided option ("?"), the scale uses a balanced structure comprising 16 positively worded and 16 negatively worded (reverse-scored) items, yielding a composite score ranging from 32 to 160. Factor-analytic investigations have validated both a two-factor model (distinguishing general unitive experience from religious interpretation) and a widely endorsed three-factor model that differentiates between extrovertive mysticism, introvertive mysticism, and religious interpretation. Demonstrating high internal consistency (Cronbach's α typically ranging from .85 to .93 for the full scale), robust convergent validity with measures of hypnotic susceptibility, transliminality, and absorption, as well as distinct discriminant validity against severe psychopathology and social desirability bias, the M Scale remains the global benchmark for empirical research across the psychology of religion, consciousness studies, neurotheology, and contemporary psychedelic-assisted psychotherapy.

Keywords

Mysticism Scale, Hood M Scale, mystical experiences, altered states of consciousness, Walter Terence Stace, extrovertive mysticism, introvertive mysticism, unitive consciousness, religious interpretation, psychometrics, psychedelic research, psychology of religion

Authors

The Mysticism Scale was developed by Ralph W. Hood, Jr., Ph.D., Professor of Psychology and Leroy A. Martin Distinguished Professor of Religious Studies at the University of Tennessee at Chattanooga (UTC). Dr. Hood is an internationally recognized authority in the psychology of religion, a past president of Division 36 (Society for the Psychology of Religion and Spirituality) of the American Psychological Association (APA), and a former co-editor of the Journal for the Scientific Study of Religion and the Archive for the Psychology of Religion. His empirical, theoretical, and phenomenological investigations span several decades, addressing topics such as mystical experience, religious fundamentalism, serpent-handling sects, and methodological frameworks for assessing transcendent subjective states.

Purpose

The primary purpose of the Mysticism Scale: Research Form D is to operationalize and quantitatively measure self-reported mystical states of consciousness without confounding the direct phenomenological report with mandatory theological or sectarian commitments. Prior to Hood's work in 1975, the scientific study of mysticism was largely confined to historical, qualitative, or philosophical analyses. Scholars such as William James in The Varieties of Religious Experience (1902) and Rudolf Otto in The Idea of the Holy (1917) had articulated the profound significance of unitive and numinous states, yet clinical and experimental psychologists lacked a standardized, standardized self-report tool capable of capturing these fleeting subjective phenomena.

Hood constructed the instrument to test the "common core" hypothesis articulated by philosopher Walter T. Stace (1960), which posits that mystical experiences share invariant phenomenological characteristics across diverse cultural, linguistic, geographical, and theological traditions. By providing an empirically rigorous measure, the M Scale enables investigators to evaluate whether reports of transcendent unity reflect universal cognitive-affective configurations or are entirely artifacts of socio-linguistic conditioning. The tool was developed to differentiate experiential core phenomena (the direct apprehension of oneness, spacelessness, and ego dissolution) from interpretative frameworks (the subsequent attribution of theological, divine, or secular meaning to that experience).

In contemporary research, the M Scale serves multiple vital functions across diverse disciplines:

• Experimental Neuropharmacology and Psychedelic Science: The M Scale is extensively utilized as a primary outcome measure in clinical trials assessing the therapeutic efficacy of psychedelic compounds such as psilocybin, DMT, and LSD (e.g., studies conducted at Johns Hopkins University, Imperial College London, and New York University). Research indicates that high M Scale scores during drug sessions strongly predict sustained reductions in treatment-resistant depression, end-of-life anxiety, and substance use disorders.
• Psychology of Religion and Cross-Cultural Studies: The scale allows researchers to examine how spiritual and secular populations experience transcendent states, demonstrating measurement invariance across Christians, Muslims, Hindus, Buddhists, and non-believers.
• Cognitive and Affective Neuroscience: Neuroimaging studies employ the M Scale to correlate specific neurobiological markers—such as decreased default mode network (DMN) functional connectivity—with self-reported unitive consciousness, ego-dissolution, and altered temporal perception.
• Differential Clinical Diagnosis: The scale aids in distinguishing healthy, integrative mystical experiences from acute psychotic decompensation, religious delusions, and schizotypal symptom clusters.

Psychological Construct

The psychological construct captured by the Mysticism Scale is defined as an intense, transient altered state of consciousness characterized by an experiential dissolution of standard psychological boundaries (ego-death), a direct apprehension of unity or oneness, and a profound shift in epistemic and affective processing. Rather than treating mysticism as an idiosyncratic religious belief system, Hood operationalized mysticism as an experiential state comprising eight phenomenological categories derived from Stace's (1960) taxonomy:

1. Ego Quality (Loss of Self)

Ego Quality assesses the dissolution of conventional self-boundaries, subjective identity, and personal agency. The respondent experiences their individual ego merging into a vast, transcendent continuum, or, conversely, entering an absolute experiential "void" devoid of mental contents. Items 3, 4, 6 (reverse), and 24 (reverse) evaluate this dimension (e.g., feeling that something greater than oneself has absorbed the personal self).

2. Unifying Quality (Perceptions of Oneness)

Unifying Quality reflects the central hallmark of the mystical state: the profound realization of universal interconnectedness. The individual perceives all distinct entities, events, and individuals as manifestation of an underlying, indivisible unity. Operationalized by items 12, 19, 28 (reverse), and 30 (reverse), this quality captures both the cognitive and perceptual recognition that "all is one."

3. Inner Subjective Quality (Living Nature / Universal Consciousness)

Inner Subjective Quality corresponds to the direct apprehension of interiority, awareness, or animacy within the external phenomenal world. In this state, external objects, physical environments, and nature are perceived not as inert physical matter, but as fundamentally alive, conscious, and aware. Measured by items 8 (reverse), 10 (reverse), 29, and 31, it reflects the panpsychic or animistic dimension often associated with nature-oriented unitive states.

4. Temporal and Spatial Quality (Distortion of Time and Space)

Temporal and Spatial Quality denotes the radical alteration, suspension, or complete transcendence of conventional spatiotemporal coordinates. Individuals report that the experience is "timeless," occurring outside the linear progression of past, present, and future, or "spaceless," where physical distance, spatial extension, and geographical location become entirely meaningless. Items 1, 11, 15 (reverse), and 27 (reverse) operationalize this distortion.

5. Noetic Quality (Perception of Special Insight)

Drawing directly from William James's conceptualization, Noetic Quality refers to the immediate, non-discursive conviction that one has gained authoritative, intuitive access to ultimate reality or profound metaphysical truth. Mystical states are not experienced merely as emotional catharsis or aesthetic reverie, but as cognitive states yielding direct, unshakeable insight. Items 13, 16 (reverse), 17, and 26 (reverse) capture this sense of revealed reality.

6. Ineffability (Defiance of Linguistic Expression)

Ineffability denotes the acute subjective recognition that the nature of the experience cannot be adequately communicated, described, or preserved through ordinary linguistic, conceptual, or logical structures. The respondent reports that language is fundamentally insufficient to convey the phenomenal essence of the state. Measured by items 2 (reverse), 21 (reverse), 23, and 32, this dimension reflects an intrinsic boundary of semantic processing.

7. Positive Affect (Peace, Bliss, and Joy)

Positive Affect captures the affective core of the mystical experience, marked by profound, non-contingent joy, serenity, peace, and emotional elevation. This affective state is qualitatively distinct from ordinary sensory pleasure or situational happiness, often manifesting as an ecstatic release from suffering and existential angst. It is indexed by items 5, 7 (reverse), 18, and 25 (reverse).

8. Religious Quality (Sacredness, Wonder, and Awe)

Religious Quality encompasses the profound sense of reverence, holiness, sacredness, and awe elicited by the experience. Although these experiences can occur completely outside organized religious environments, the phenomenal quality evokes feelings traditionally associated with the divine or numinous. Operationalized by items 9 (reverse), 14 (reverse), 20, and 22, this dimension taps into the affective response to confronting something perceived as holy.

Theoretical Framework

The theoretical architecture of the Mysticism Scale rests at the intersection of comparative philosophy, phenomenological psychology, and the cognitive science of religion. Its primary intellectual foundation is Walter Terence Stace's philosophical treatise, Mysticism and Philosophy (1960). Stace advanced the "Common Core Hypothesis" (a variant of the perennial philosophy), asserting that despite radical divergence in religious doctrines, cultural backgrounds, and semantic metaphors, mystical experiences across human history exhibit an identical phenomenological core structure.

Crucially, Stace delineated two primary forms of unitive mystical experience:

• Extrovertive Mysticism: The subject looks outward through ordinary sensory perception and apprehends multiplicity as an underlying, living unity. Physical objects retain their distinct empirical forms, yet are perceived as simultaneously unified and suffused with a universal life force ("all things are one").
• Introvertive Mysticism: The subject withdraws entirely from external sensory impressions and internal mental representations (thoughts, images, memories). Sensory awareness is completely obliterated, leaving the subject conscious only of an undifferentiated, empty, spaceless, and timeless unity or "void"—pure consciousness itself.

Stace posited that introvertive mysticism represents the higher, more complete phenomenological manifestation of the mystical state, whereas extrovertive mysticism represents an incomplete or sensory-mediated apprehension of the same underlying unity. Both variants, however, share the peripheral characteristics of ineffability, noetic insight, positive affect, and a sense of sacredness.

Hood integrated Stace's taxonomy with the foundational insights of William James (1902), who defined mystical states through the fourfold criteria of Ineffability, Noetic Quality, Transiency, and Passivity. Furthermore, Hood incorporated Rudolf Otto's (1917) concept of the numinous—the non-rational encounter with the mysterium tremendum et fascinans (a mystery that simultaneously terrifies and enchants), which accounts for the deep affective qualities of sacredness, awe, and wonder captured in the instrument.

In developing the M Scale, Hood also addressed the significant philosophical critique posed by "constructivism" (most notably advanced by Steven T. Katz in 1978). Constructivists argue that there are no pure, unmediated experiences; rather, language, culture, and theological doctrine pre-form and determine the experience itself. By formulating items that separate raw phenomenal unitive experience from subsequent religious attribution, Hood provided an empirical method to test whether a universal core could indeed be detected independently of sectarian conditioning.

Validity

The psychometric validity of the Mysticism Scale has been extensively corroborated across diverse cultural, clinical, and experimental contexts over nearly five decades of research.

Construct and Convergent Validity

The construct validity of the M Scale is demonstrated by its consistent correlations with psychological constructs conceptually linked to altered states of consciousness, openness, and transpersonal orientation:

• Absorption and Openness to Experience: Hood (1975) established strong positive correlations between M Scale scores and measures of openness to experience. Subsequent research by Spanos and Moretti (1988) confirmed that the M Scale correlates significantly with the Tellegen Absorption Scale (TAS), which measures the capacity for episodes of total attentional involvement that fully engage an individual's perceptual and ideational resources.
• Hypnotizability and Transliminality: Research confirms moderate-to-high correlations between the M Scale and standardized hypnotic susceptibility scales (such as the Stanford Hypnotic Susceptibility Scale), as well as measures of transliminality (the psychological tendency for psychological material to cross the threshold into consciousness).
• Religious Motivation: Scores on the M Scale correlate moderately with Allport and Ross's Intrinsic Religious Orientation, indicating that individuals who view religion as an end in itself report higher mystical frequency than those possessing an extrinsic, utilitarian orientation.
• Experimental Validation: Laboratory studies utilizing sensory deprivation chambers (Hood, 1977) and semistructured nature experiences have reliably elicited marked increases in M Scale scores, verifying that the instrument sensitive to acute, induced experiential states.

Discriminant Validity

Crucially for clinical and psychological measurement, the M Scale demonstrates distinct discriminant validity against psychopathology and response biases:

• Social Desirability: Research by Spanos and Moretti (1988) revealed that the M Scale is unrelated to measures of social desirability (such as the Marlowe-Crowne Social Desirability Scale), confirming that high scores reflect authentic phenomenological reports rather than a tendency to present oneself favorably.
• Independence from Neuroticism and Psychopathology: Caird (1987) administered the Eysenck Personality Questionnaire alongside the M Scale, finding no significant relationship between mystical experience and either Neuroticism (N) or Psychoticism (P).
• Differentiation from Psychotic Delusions: A landmark empirical investigation by Stifler, Greer, Sneck, and Dovenmuehle (1993) directly compared three distinct populations: religiously delusional psychiatric inpatients, contemplative religious practitioners, and non-clinical control participants. While both psychotic patients and contemplative practitioners reported elevated mystical phenomena relative to controls, contemplative individuals demonstrated superior psychological integration and remarkably low psychopathology. In contrast, psychotic inpatients exhibited fragmented, distress-laden, and functionally debilitating symptom profiles, proving that mystical experience as operationalized by the M Scale is not inherently pathological.
• Positive Personality Functioning: Hood, Hall, Watson, and Biderman (1979) found self-reported mysticism to be positively associated with psychological differentiation, personal creativity, and high tolerance for ambiguity, reinforcing the concept that mystical states often support adaptive cognitive flexibility (Cowling, 1985).

Reliability

The Mysticism Scale exhibits high psychometric reliability, maintaining internal consistency and structural stability across a wide variety of demographic groups, translation languages, and administration modalities.

Internal Consistency

In his original instrument development study comprising 300 university undergraduates, Hood (1975) established that the 32-item scale possessed substantial internal consistency. Corrected item-total correlations across the 32 items ranged from a low of .29 (Item 2) to a high of .55 (Item 28), with an overall Cronbach's alpha typically exceeding .85 for the omnibus instrument. Subsequent investigations across international and non-student cohorts have regularly reported overall alpha coefficients between .88 and .93.

Reliabilities for subscales derived from factor analytic solutions also meet or exceed psychometric benchmarks:

• Hood et al. (1993) Three-Factor Model: In a sample of 740 participants, Cronbach's alpha coefficients were computed at .76 for the Extrovertive Mysticism factor, .69 for the Introvertive Mysticism factor, and .76 for the Religious Interpretation factor.
• Cross-Cultural Replications: In large-scale cross-cultural investigations involving American and Iranian samples (Hood et al., 2001), internal consistencies for the three components remained highly satisfactory, ranging from .70 to .82 across diverse linguistic and theological cohorts.

Test-Retest Stability

Because the M Scale assesses lifetime occurrences of intense subjective experiences, scores reflect a combination of lifetime trait reporting and acute state responsiveness. Longitudinal assessments across intervals ranging from two to eight weeks have yielded test-retest reliability coefficients ($r$) between .78 and .86, demonstrating robust temporal stability in non-experimental settings where no consciousness-altering interventions occur.

Factor Analysis

The latent structure of the Mysticism Scale has undergone extensive empirical evaluation, resulting in three primary structural models that continue to inform quantitative scholarship.

Hood's Original Two-Component Solution (1975)

Using principal components analysis with varimax rotation on the initial validation sample, Hood (1975) identified an overarching two-component structure:

• Factor 1: General Mystical Experience / Intense Unity (20 items): Encompassing items 1, 2, 4, 6, 8, 10, 11, 12, 15, 18, 19, 21, 23, 24, 27, 28, 29, 30, 31, and 32. This factor loaded heavily on items reflecting core phenomenological criteria: unity, ineffability, ego dissolution, and spatiotemporal transcendence.
• Factor 2: Religious Interpretation / Affective Insight (12 items): Encompassing items 3, 5, 7, 9, 13, 14, 16, 17, 20, 22, 25, and 26. This factor loaded on items denoting religious interpretation, sacredness, wonder, awe, and positive affective states.

Caird's Alternative Three-Factor Model (1988)

Caird (1988) conducted an independent factor analysis ($N = 115$), proposing a three-factor solution that retained a general unitive core factor while dividing the interpretive component into two distinct subscales: one focused on overtly religious attributions and another focused on noetic, knowledge-based insights.

The Landmark Hood, Morris, and Watson Three-Factor Solution (1993)

Based on a substantially larger and more diverse empirical sample ($N = 740$), Hood, Morris, and Watson (1993) demonstrated that Stace's theoretical distinction between extrovertive and introvertive mysticism could be cleanly recovered via exploratory factor analysis. This three-factor model is currently considered the gold standard for structural research:

• Factor 1: Extrovertive Mysticism (12 items): Items 6, 8, 10, 12, 15, 19, 24, 27, 28, 29, 30, 31. Captures unitive consciousness mediated through sensory reality, where the external world is experienced as alive, conscious, and unified into an indivisible whole.
• Factor 2: Religious Interpretation (12 items): Items 5, 7, 9, 13, 14, 16, 17, 18, 20, 22, 25, 26. Captures the affective, noetic, and sacred qualities of the experience, including profound joy, peace, awe, and perceived encounters with ultimate or divine reality.
• Factor 3: Introvertive Mysticism (8 items): Items 1, 2, 3, 4, 11, 21, 23, 32. Captures pure, non-sensory unitive consciousness characterized by timelessness, spacelessness, ego absorption, consciousness of a "void," and complete ineffability.

Confirmatory Factor Analysis and Structural Invariance

Subsequent confirmatory factor analyses (CFA) have verified that the three-factor solution demonstrates superior model fit compared to unifactorial or two-factor models across cross-cultural and cross-religious samples. Goodness-of-fit indices (RMSEA < .06, CFI > .90, TLI > .90) confirmed measurement invariance across American Christian, Iranian Muslim, and secular Western cohorts (Hood et al., 2001; Chen et al., 2011). These findings strongly reinforce Stace's thesis that extrovertive unity, introvertive void/spacelessness, and interpretative framing represent distinct, cross-culturally replicable dimensions of transcendent consciousness.

Instrument / Measurement Tool

• Test Type: Standardized self-report psychometric scale; available in retrospective lifetime inventory format or acute session-state variant.
• Primary Developer: Ralph W. Hood, Jr. (1975).
• Item Count: 32 items.
• Target Population: Adolescents and adults (typically 16+ years); nonsectarian and nonsexist item wording allows universal administration across clinical, secular, and diverse theological populations.
• Administration Format: Self-administered paper-and-pencil questionnaire, digital web-based assessment, or structured oral interview (employing a binary yes/no response format if required).
• Administration Time: Approximately 8 to 12 minutes.
• Response Format: 5-point Likert-type scale with numerical and descriptive anchoring:
  • +2: This description is definitely true of my own experience or experiences.
  • +1: This description is probably true of my own experience or experiences.
  • ?: I cannot decide (mathematically treated as 0).
  • -1: This description is probably not true of my own experience or experiences.
  • -2: This description is definitely not true of my own experience or experiences.
• Scoring and Transformation Rules:
  1. Reverse Scoring: Half of the items (16 items) are negatively worded to protect against acquiescence bias. Reverse the raw values of the following 16 items: 2, 6, 7, 8, 9, 10, 14, 15, 16, 21, 24, 25, 26, 27, 28, 30. (For example, a raw rating of -2 becomes +2, -1 becomes +1, ? remains 0, +1 becomes -1, and +2 becomes -2).
  2. Rescaling: Add a constant of 3 to each item score (including reverse-scored values and "?" entries). Following transformation: -2 = 1 point; -1 = 2 points; ? (0) = 3 points; +1 = 4 points; +2 = 5 points.
  3. Composite Summation: Sum all 32 transformed item scores. Total scale scores range from a minimum of 32 to a maximum of 160.
• Subscale Scoring (3-Factor Model):
  • Extrovertive Mysticism: Sum transformed scores of items 6, 8, 10, 12, 15, 19, 24, 27, 28, 29, 30, 31 (Score range: 12 to 60).
  • Religious Interpretation: Sum transformed scores of items 5, 7, 9, 13, 14, 16, 17, 18, 20, 22, 25, 26 (Score range: 12 to 60).
  • Introvertive Mysticism: Sum transformed scores of items 1, 2, 3, 4, 11, 21, 23, 32 (Score range: 8 to 40).
• Interpretation: Higher scores denote a higher frequency and intensity of reported mystical experiences. In clinical psychedelic trials, achieving a score equal to or exceeding 60% of the maximum possible points on all subscales is routinely adopted as the criterion for a "complete mystical experience."

Permissions & Fee and Test Year

The Mysticism Scale: Research Form D was originally published in 1975 in the Journal for the Scientific Study of Religion by Dr. Ralph W. Hood, Jr. The instrument is considered an open-access, public-domain psychometric scale for non-commercial, academic, scientific, and clinical research purposes. No royalty fees or formal licensing agreements are required for academic investigators utilizing the scale, provided appropriate academic citation is accorded to Hood (1975) and subsequent validation studies. For commercial applications, proprietary assessment batteries, or digital health platform integration, researchers should consult standard institutional permissions or directly contact Dr. Ralph W. Hood, Jr. at the Department of Psychology, University of Tennessee at Chattanooga.

References

• Caird, D. (1987). Religiosity and personality: Are mystics introverted, neurotic, or psychotic? British Journal of Social Psychology, 26(4), 345–346. https://doi.org/10.1111/j.2044-8309.1987.tb00798.x
• Caird, D. (1988). The structure of Hood's Mysticism Scale: A factor-analytic study. Journal for the Scientific Study of Religion, 27(1), 122–127. https://doi.org/10.2307/1387407
• Chen, Z., Hood, R. W., Jr., Yang, L., & Watson, P. J. (2011). Mystical experience among Tibetan Buddhists: The Mysticism Scale revisited. Psychology of Religion and Spirituality, 3(4), 298–310. https://doi.org/10.1037/a0024479
• Cowling, W. R. (1985). Relationship of mystical experience, differentiation, and creativity. Perceptual and Motor Skills, 61(2), 451–456. https://doi.org/10.2466/pms.1985.61.2.451
• Hood, R. W., Jr. (1975). The construction and preliminary validation of a measure of reported mystical experience. Journal for the Scientific Study of Religion, 14(1), 29–41. https://doi.org/10.2307/1384454
• Hood, R. W., Jr. (1977). Eliciting mystical states of consciousness with semistructured nature experiences. Journal for the Scientific Study of Religion, 16(2), 155–163. https://doi.org/10.2307/1385746
• Hood, R. W., Jr., Ghorbani, N., Watson, P. J., Ghramaleki, A. F., Bing, M. N., Davison, H. K., Morris, R. J., & Williamson, W. P. (2001). Dimensions of the Mysticism Scale: Confirming the three-factor structure in the United States and Iran. Journal for the Scientific Study of Religion, 40(4), 691–705. https://doi.org/10.1111/0021-8294.00085
• Hood, R. W., Jr., Hall, J. R., Watson, P. J., & Biderman, M. (1979). Personality correlates of the report of mystical experience. Psychological Reports, 44(3), 804–806. https://doi.org/10.2466/pr0.1979.44.3.804
• Hood, R. W., Jr., Morris, R. J., & Watson, P. J. (1990). Quasi-experimental elicitation of the differential report of religious experiences among intrinsic and indiscriminately pro-religious types. Journal for the Scientific Study of Religion, 29(2), 164–172. https://doi.org/10.2307/1387429
• Hood, R. W., Jr., Morris, R. J., & Watson, P. J. (1993). Further factor analysis of Hood's Mysticism Scale. Psychological Reports, 73(3_suppl), 1176–1178. https://doi.org/10.2466/pr0.1993.73.3f.1176
• Hood, R. W., Jr., Spilka, B., Hunsberger, B., & Gorsuch, R. (1996). The psychology of religion: An empirical approach (2nd ed.). Guilford Press.
• James, W. (1902). The varieties of religious experience: A study in human nature. Longmans, Green, and Co. https://doi.org/10.1037/10004-000
• Otto, R. (1917). Das Heilige: Über das Irrationale in der Idee des Göttlichen und sein Verhältnis zum Rationalen [The Idea of the Holy]. Trewendt & Granier.
• Spanos, N. P., & Moretti, P. (1988). Correlates of mystical and diabolical experiences in a sample of female university students. Journal for the Scientific Study of Religion, 27(1), 105–116. https://doi.org/10.2307/1387405
• Stace, W. T. (1960). Mysticism and philosophy. J. B. Lippincott Company.
• Stifler, K. R., Greer, J., Sneck, W., & Dovenmuehle, R. (1993). An empirical investigation of the discriminability of reported mystical experiences among religious contemplatives, psychotic inpatients, and normal adults. Journal for the Scientific Study of Religion, 32(4), 366–372. https://doi.org/10.2307/1386580

Items of the Scale