Harold E. Puthoff, PhD Sources:

Harold E. Puthoff is a physicist who jointly led the remote-viewing research programme at Stanford Research Institute (SRI) with Russell Targ.[1] Trained in laser physics, he earned his PhD from Stanford University in 1967 and joined SRI in 1971.[2] With Targ he introduced the term “remote viewing” for the reported ability of individuals to describe distant locations blocked from ordinary perception, and the pair published the programme’s early results in Nature and the Proceedings of the IEEE.[3][4] He founded the Institute for Advanced Studies at Austin in 1985, which he directs, and is President, CEO and Chairman of the Board of EarthTech International.[1]

Overview

The SRI programme asked a plainly stated question: can a person in a laboratory describe a distant place or a hidden object well enough that independent judges, visiting the sites without knowing the answers, can match the descriptions to the right targets? Puthoff and Targ framed the goal as building a stable data base of cause-and-effect relationships, not a catalogue of interesting anecdotes.[3]

Three claims anchored the work. First, blind judges matched viewer descriptions to target sites far more often than chance allowed.[5] Second, accuracy did not appear to depend on distance, which was varied from a few kilometres up to several thousand kilometres.[8][5] Third, electromagnetic shielding around the viewer did not visibly degrade the descriptions, which the authors argued casts doubt on explanations based on conventional radio propagation.[8][5] The same papers state plainly that the descriptions contained errors alongside accurate detail: an imperfect channel carrying noise as well as signal.[3]

Puthoff came to this research from mainstream physics rather than psychology, and much of the SRI work was carried out for U.S. government sponsors; a 1980 SRI final report that he co-authored was produced under the classified “Grill Flame” special access programme and has since been declassified.[2][7][1]

The 51-Experiment Data Base

The 1976 Proceedings of the IEEE review tabulated 51 double-blind remote-viewing experiments with nine subjects: six in the formal study and three visiting government scientists.[5] The sum-of-ranks evaluation across the full set was significant at p = 10−5; sub-series ranged from p = 2.9 × 10−5 for the nine-trial Price series to p = 0.036 for the twelve-trial indoor technology series, and the two learner subjects S5 and S6 did not reach significance (p = 0.08).[5] The Faraday cage used in several series provided 120 dB attenuation for plane-wave radio-frequency radiation over 15 kHz to 1 GHz; for magnetic fields the attenuation fell from 68 dB at 15 kHz to 3 dB at 60 Hz, so extremely low frequencies were not fully excluded — a limitation the authors themselves discussed when weighing the ELF-carrier hypothesis.[3][4]

Life and career

Puthoff’s training was entirely in mainstream physics and engineering. He holds bachelor’s and master’s degrees in electrical engineering from the University of Florida and a PhD from Stanford University, awarded in 1967.[2][1] From 1960 to 1963 he served as a U.S. Navy officer in a research capacity; he lectured at Stanford from 1969 to 1970 and joined SRI in 1971 as a specialist in laser physics after eight years of research in Stanford’s Microwave Laboratory.[2] His research career also included General Electric, Sperry, and the National Security Agency.[1]

At SRI his work broadened from lasers to what the laboratory called psychoenergetics. He and Targ ran the remote-viewing programme jointly, and classified psi research at SRI also involved physicist Edwin May.[1][9] The artist Ingo Swann, who wrote to Puthoff in March 1972 after reading one of his research proposals, became the programme’s most prominent participant and later described Puthoff as the project’s head.[10][11]

In 1985 Puthoff founded the Institute for Advanced Studies at Austin, which was incorporated under EarthTech International in 1991; Swann’s account records that Puthoff headed the SRI project until accepting the Austin position.[1][11] His subsequent physics spans theoretical work on fundamental electrodynamics, gravitation, and the quantum vacuum, together with laboratory work on energy generation and space propulsion.[1] He was named a Fetzer Fellow in 1991 and a Fellow of the British Interplanetary Society in 2012.[1]

Physics Credentials and Selected Publications

Puthoff holds patents in lasers and optical devices, supervised doctoral research in electrical engineering and applied physics at Stanford, and co-authored the textbook Fundamentals of Quantum Electronics with R. H. Pantell (1969), a text bridging quantum mechanics with engineering.[2] His own publication list runs to two 2016 physics papers, one in Eur. J. Phys. on electromagnetic potentials and one in Quant. Stud.: Math. Found. on quantum ground states, alongside his historical account of the CIA-initiated remote-viewing programme.[1] That historical account, “CIA-Initiated Remote Viewing Program at Stanford Research Institute,” appeared in the Journal of Scientific Exploration in 1996.[12][1]

Research

Puthoff’s psi research divides into four strands: free-response remote viewing of natural targets, perception experiments under sensory shielding, instrumented psychokinesis studies, and government-sponsored training and applied protocols. A fifth strand, running through all of them, is his attempt to frame the results in the language of physics.[5][2]

Remote viewing of natural targets

The standard experiment closeted a viewer with an interviewer at SRI while a target team travelled to a site drawn by random protocol from a pool held by an SRI division director; neither the viewer nor the interviewer knew the target or the pool’s contents.[3] The viewer’s tape-recorded impressions and drawings were later matched, blind, against the sites by independent judges.[3] In plain terms, judges walking the sites could usually tell which transcript belonged to which place.[3][5] The initial Price series was followed by a comparable series with Hella Hammid, a professional photographer with no prior sense of psychic ability, whose series was judged even more sharply; two further experienced subjects also produced significant series, while a pair of learner volunteers did not reach significance.[5]

The design named and addressed specific non-psi explanations. Interviewer cueing was eliminated by keeping the interviewer ignorant of both the target and the pool, so questions could not steer the viewer.[3] The worry that generic “grass is green, sky is blue” transcripts would fit every target was handled by differential blind matching, in which a transcript scores only if judges can distinguish it from the other transcripts across all sites.[7] A residual confound — viewers gradually learning the pool’s contents across a series — was handled statistically by conservatively assuming the pool was fully known in advance to everyone involved.[7]

Judging Methods and Series Statistics

Judges blind rank-ordered each transcript against each site; significance was computed from the sum of ranks on the correct pairings, or by an exact direct-count-of-permutations method requiring no distributional assumptions.[5][7] Price’s nine-trial series produced a sum of ranks of 16 with seven direct hits (p = 2.9 × 10−5); Hammid’s nine-trial series produced a sum of 13 with five direct hits and four second ranks (p = 1.8 × 10−6); the combined eight-trial series with experienced subjects Elgin and Swann reached p = 3.8 × 10−4; the learner pair’s combined series was non-significant at p = 0.08; and five trials with two visiting government scientists reached p = 0.017.[5] Hammid and Elgin came out of a 147-volunteer NASA-programme screening, selected by different performance criteria.[8] Drawings were generally more accurate than verbal descriptions, and correct material tended to concern shape, form, colour, and material rather than the target’s name or function.[5] The reliance on blind human matching of free-response material makes signal-detection methodology — the mainstream framework for judging hits against statistical baselines — the relevant modern comparator.[13] The SRI protocols themselves instructed viewers that memory and imagination constitute noise in the channel; mainstream source-monitoring research documents how imagination and memory can be misattributed as perception, the exact failure mode the protocol tried to suppress.[7][14]

Perception under sensory shielding

With Uri Geller, Puthoff and Targ ran thirteen picture-reproduction experiments over seven days, with Geller visually, acoustically, and electrically shielded and targets drawn only after his isolation.[3] Two blind judges matched all ten of his submitted responses to the correct target drawings without error.[3] The same Nature paper reports the failures with equal prominence: a follow-up series of one hundred sealed-envelope targets known to no person produced drawings that did not depart from chance, and although metal bending by Geller was observed informally in the laboratory, the authors state they were never able to combine such observations with adequately controlled experiments.[3]

A separate EEG study asked whether a remote stimulus could register physiologically even without awareness. When a distant sender viewed trains of light flashes, a shielded receiver’s alpha rhythm dropped measurably, yet her conscious guesses about when the flashes occurred stayed at chance — arousal, the authors concluded, only at a noncognitive level.[3]

Shielding, Targets, and Controls

Geller’s shielded-room targets were selected by three methods: arbitrary dictionary entry, independent preparation by outside SRI scientists after his isolation, and advance target pools; in the trial where the person-to-person link was fully removed (a picture locked in the room before his arrival, with the artist gone), Geller reported no clear impression and submitted no drawing.[3] In a double-blind die-in-a-steel-box task he passed twice and answered eight times, correctly on all eight.[3] In the EEG study, seven 36-trial sets with subject H.H. showed average alpha power reduced by 24% (p < 0.04) and peak power by 28% (p < 0.03) during 16-flash-per-second remote stimulation relative to no-flash periods; control recordings from a saline solution with a 12-kilohm resistance in place of the subject showed no flash-frequency artifacts, and further tests found no radio-frequency energy associated with the stimulus, ruling out system artifacts for those checks.[3] Modern methodological work on researcher degrees of freedom in psychophysiology — window selection, baseline definition, outlier rules — identifies the analytic-flexibility regime in which small effects of this kind must now be evaluated.[15]

Instrumented psychokinesis studies

Puthoff’s first psychoenergetics observation at SRI, in 1972, was an apparent perturbation of a superconductor-shielded magnetometer while Ingo Swann directed attention at it; Puthoff and Targ labelled this an observation rather than a controlled experiment and listed the checks it lacked, including too few data samples for statistics and no test for recorder-only effects.[6][2] A longer controlled series with a superconducting differential gradiometer then found that instrument events correlated significantly with Pat Price’s randomly scheduled effort periods from four metres (about 13 feet) away.[6] Pilot work with a laser-monitored torsion pendulum and with a low-energy electron beam produced on-command changes the authors described as suggestive, explicitly pending statistical analysis over larger control samples.[6][2]

Artifact handling was specific rather than generic. A truck passing the adjacent parking lot was logged and identified as an artifact in one gradiometer period; radio-frequency bursts were acknowledged as possible contaminants and handled through the statistical correlation design; and recorder-only effects were judged low probability because signals appeared simultaneously on three recording devices — while the authors conceded that an electronics interference effect upstream of all displays could not be fully ruled out.[6] Vibrational artifacts on the pendulum were separable by signature, since environmental jolts drove a 1-Hz vertical oscillation distinct from the 0.1-Hz torsional mode under study.[6]

Instruments and Effect Details

The magnetometer was a SQUID device in a well beneath a building, shielded by mu-metal, aluminium, copper, and a superconducting niobium shield; during Swann’s session the calibration output doubled in frequency for roughly 30 seconds and then flattened for roughly 45 seconds on request, with over an hour of clean traces before and after.[6][2] The gradiometer series comprised 13 ten-trial runs (130 trials: 64 activity, 66 no-activity periods); of 63 events with signal-to-noise ratio above one, 42 fell in activity periods and 21 in no-activity periods, a correlation significant at p = 0.004, with each on-scale signal corresponding to about 1.6 × 10−9 G/cm².[6] The torsion pendulum, sealed under a bell jar and read out by laser to roughly 10-microradian sensitivity, showed change-to-baseline ratios of about 5:1 with the subject one metre (about 3 feet) away and about 2:1 from a room 12 metres (about 39 feet) down the hall.[6] In the electron-beam experiment, a subject seated 1.8 metres (six feet) from the tube in a screened room produced galvanometer deflections during test intervals but not control intervals.[2]

Government-sponsored training and applied protocols

A 1980 SRI final report by Targ, Puthoff, Beverly Humphrey, and Edwin May, produced under the Grill Flame special access programme, describes a one-year effort to transfer the SRI remote-viewing protocols to six volunteers selected by the client organization.[7] Four of the six produced individually significant series on local target sites, and performance on that first screening series tracked later performance on other tasks.[7] The report also explored 35-mm slide targets, “future remote viewing” of targets not yet chosen, extended remote viewing of objects held in a secure facility, alphabet-letter targets, and coordinate remote viewing from latitude and longitude alone.[7] It is candid where results fell short: no future-remote-viewing series reached statistical significance, despite individually striking trials.[7]

The 1979-1980 Orientation Programme

Screening ran in stages: the sponsor considered 250 candidates, interviewed 117, formed a pool of 30-35, sent ten to SRI interview, and six were chosen — selection by personality profile (confident, outgoing, adventurous, with some artistic bent) after formal medical and psychological test batteries in earlier work had yielded no usable predictive profile.[7] In Phase One, each volunteer ran six local-site trials; four series were individually significant (each at p = 0.003 or better), making the group result p = 4 × 10−5, and more than half of the 36 transcripts were first-place matched in blind judging.[7] Phase Two results included slide viewing at p = 0.017 for one viewer and p < 0.04 (pictorial responses alone) for another; an extended-remote-viewing object series judged significant at p = 0.05 by one of two analysts; six of 27 alphabet letters correctly identified in a consistent-protocol pilot; and a coordinate remote-viewing series of 21 assessable targets significant at p = 0.0083.[7] A post-hoc 0-7 accuracy-rating scale correlated with formal blind judging at r = 0.59 (p = 5 × 10−5) across the 36 Phase-One transcript-target pairs.[7] The report’s methodological core is the viewer/interviewer division of labour, with the interviewer carrying the analytical burden, and the instruction to report raw imagery rather than interpretation.[7]

Theoretical models

In a 1974 chapter of Edgar Mitchell’s Psychic Exploration, Puthoff and Targ proposed a testable model of precognition built on the “advanced-potential” solutions of classical field equations — mathematically valid solutions ordinarily discarded because they run backward in time — and predicted that precognitive accuracy should fall off with temporal distance from the event.[2] For psychokinesis, Puthoff speculated that a subject may act as a “local negentropic source” (the paper’s own term), ordering a system’s noise or manipulating boundary conditions rather than supplying energy; he presented these as hypotheses for designing experiments, not as conclusions from the data.[6] This separation of data from proposed mechanism runs through his papers: the experimental correlations are reported on their own terms, and the physics is labelled speculation.[6][2]

Mainstream physics offers relevant counterweights to the quantum framing. Tegmark’s decoherence calculations argue that quantum coherence cannot survive in the warm, wet brain, a direct physics-based challenge to consciousness-collapse mechanisms.[16] Surveys of working physicists find that consciousness-causes-collapse interpretations of quantum mechanics are held by a small minority.[17] And quantum-eraser experiments show that which-path information, not a conscious observer, is what destroys interference — the mainstream baseline against which any observer-effect analogy of the kind Puthoff floated must be measured.[18]

The ESP-Teaching Machine and the Advanced-Potential Model

The four-choice ESP-teaching machine scaled through its internal states at 250 kilohertz, offered a pass option to remove forced choice, and gave immediate feedback; its randomness was verified over 2,400 trials.[2] Most of the 12 unscreened subjects showed no improvement, but the best subject completed 64 runs of 24 trials with a mean of 8.6 hits per run against 6 expected, a result the authors put at roughly p = 10−15.[2] Switched to a precognitive mode with a 0.2-second delay before target selection, the same subject improved from 19 hits in her first 96 trials to 38 in her last 96; a linear regression over 672 trials gave a slope of 2.24 hits per 96-trial block and a correlation coefficient of 0.51 (about 1 in 200 by chance), which the authors read as suggestive of learning.[2] The advanced-potential model, drawing on Stratton’s treatment of the discarded time-advanced solutions of the moving-charge equations, predicts that the most commonly precognized events should be large, attention-catching, and very close in time — the authors’ example being waking seconds before an alarm rings.[2]

Skeptic perspectives and rebuttals

Experiments that are not designed to be “fraud-proof” cannot serve as conclusive proof of ESP, whether or not fraud actually occurred.

Skeptic source: C. E. M. Hansel, ESP: A Scientific Evaluation (1966), whose in-principle fraud argument Puthoff and Targ quote and discuss in their 1976 review.[4]

Response: The 1976 Proceedings of the IEEE paper answers three anticipated flaws by name: cueing was addressed by double-blind protocols in which no one in contact with the subject knew the target; selective reporting was addressed by a master log on which every experiment was entered as performed and included in the statistics; and data editing was addressed by submitting complete, unedited tape-recorded data packages for blind judging.[4]

Analysis. Hansel’s 1966 argument addressed the in-principle possibility of fraud in earlier card-guessing series at Duke and by Soal, not any documented incident at SRI. Puthoff and Targ’s 1976 paper responds with named protocol features: independent target selection by an SRI division director, blind judging by analysts outside the research group, and complete logging of every trial. Dunne and Bisaha’s Chicago-area replication with volunteer participants reported significant results generated outside the SRI laboratory.[19]

David Marks and co-authors published book-length and journal critiques challenging the SRI remote-viewing experiments.

Skeptic source: Marks & Kammann, The Psychology of the Psychic (1980), and Marks & Scott, “Remote viewing exposed,” Nature, 319 (1986), both catalogued in the reference apparatus of works in this corpus.[20][9]

Response: Tart, Puthoff, and Targ published a 1980 Nature note on information transmission in remote-viewing experiments.[21] Dean Radin‘s later survey states that detailed examinations of the critiques of the Nature-published SRI work found them unable to explain away the reported results, and that Targ, Edwin May, and others subsequently replicated remote viewing under controlled conditions.[9]

Analysis. The published exchange spans Marks and Kammann’s 1980 book, the 1980 Nature note by Tart, Puthoff, and Targ, and Marks and Scott’s 1986 Nature commentary. The specific arguments of the skeptic publications are not reproduced in the sources cited on this page, so this entry documents the exchange rather than its content. Radin’s assessment appears in a book written in support of psi research; the primary skeptic texts remain the artifacts a reader would need to consult directly.[9]

The 1976 Paper’s Self-Audit of Potential Flaws

Puthoff and Targ’s 1976 review anticipates the three standard critiques — naive protocol permitting cueing, selection of successful experiments from a larger pool, and post-hoc editing of data — and answers each with a concrete procedural claim: double-blind target handling, a master log guaranteeing that every experiment performed enters the evaluation, and unedited transcripts and drawings in the judged data packages.[4] The 1980 report goes further on the guessing problem, applying an exact statistical method that conservatively treats the target pool as fully known in advance to viewer and interviewer alike, so that any pool-familiarity advantage is priced into the null hypothesis.[7]

Influence and reception

The term Puthoff and Targ introduced travelled well beyond SRI. Brenda Dunne conducted a replication of the SRI experiments in the Chicago area using inexperienced volunteers rather than claimed psychics, with results reported as highly significant; that work became the impetus for the remote-perception component of Princeton’s PEAR programme.[19] Puthoff’s own 1980 report cites the Mundelein College precognitive remote-viewing replications by Bisaha and Dunne, including trials with viewers in Chicago and the outbound experimenter in the Soviet Union.[7]

Government engagement with the SRI work ran for roughly two decades and was later declassified under programme names including GRILL FLAME, CENTER LANE, SUN STREAK, and STAR GATE.[9] At the request of Congress and the Central Intelligence Agency, the American Institutes for Research commissioned evaluations of the government-sponsored research conducted at SRI International and Science Applications International Corporation, with statistician Jessica Utts and psychologist Ray Hyman preparing the assessments.[22]

Within the field, Ingo Swann dedicated his book Everybody’s Guide to Natural ESP to Puthoff, crediting his persistence through years of external criticism of the SRI programme, and wrote that the SRI experimental design had been copied by researchers worldwide with similar results.[11] Free-response psi designs of the remote-viewing kind remain a subject of formal meta-analysis; Storm and Tressoldi reviewed free-response studies published between 2009 and 2018.[23] The Open Science Collaboration’s large replication audit of psychology, in which most sampled effects failed to replicate, now frames how any small behavioural effect — psi or otherwise — is evaluated across independent laboratories.[24]

Replication and Evaluation Record

Radin’s summary of the PEAR remote-perception programme reports 653 formal trials with 72 participants conducted from 1976 to 1999, most run precognitively, with a composite result Jahn and Dunne put at odds against chance of 33 million to 1.[9] The AIR evaluation covered the SRI and SAIC government-sponsored research and was framed around whether the work merited continued government funding; the corpus includes Utts’s assessment, which references the SRI technical reports co-authored by Puthoff and Targ.[22] Puthoff’s own retrospective on the programme’s origins appeared as “CIA-Initiated Remote Viewing Program at Stanford Research Institute” in the Journal of Scientific Exploration (1996).[12]

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