JOHN PALMER 
ABSTRACT: Two series are reported in which subjects could use psi to continue playing computer solitaire and possibly win a $100 prize. Subjects were told nothing about using psi for this purpose. After they recorded their scores for each set of four games, a pseudo-random algorithm activated by a keyboard button press determined if they could continue. The principal psi measure was the number of sets of solitaire completed. ESP scores in Series I for 48 subjects were nonsignificant, and the only significant post-hoc finding was a positive correlation between the number of sets completed and a question asking how much the subject desired to get a high score. Several procedural modifications were introduced in Series II, most notably use of a hardware RNG, which generated either 20 or 200 numbers. The average number of sets completed by the 50 subjects was once again nonsignificant, but the mean overall standard score based on the RNG output was suggestively above chance (p = .057) and significantly above-chan ce (p = .015) for the 20-trial condition. The squared standard scores correlated positively with the addiction scale of the Solitaire Questionnaire (p = .010), confirming the PMIR hypothesis that the most highly motivated subjects should demonstrate the most psi.
Numerous psi experiments have demonstrated that psi can occur without the intention of the ostensible psi source (e.g., Berger, 1988; Weiner & Zingrone, 1986; West & Fisk, 1953), who may not even be told that psi is involved in the experiment (e.g., Nelson, Bradish, Dobyns, Dunne, & Jahn, 1996; Stanford, Zenhausern, Taylor, & Dwyer, 1976). In theory such a situation might be advantageous, because subjects' doubts about their ability to succeed, which may precipitate either chance scoring or psi-missing, will not arise. In his psi-mediated instrumental response (PMIR) model, Stanford (1977) postulates that subjects must be supplied with some sort of motivation if they are to apply their psi abilities. As the desire to demonstrate psi is not engaged in a covert psi task, some sort of extrinsic motivation must be supplied in such situations.
Investigators in recent years have sometimes turned to computer games to aid in motivating subjects in ordinary psi experiments (e.g., Broughton & Perlstrom, 1986, 1992), and there is no reason why such games cannot be used in covert psi experiments as well. A computer game that I thought would have particular potential in this regard is computer solitaire. First, the game is supplied free of charge with the widely used Microsoft Windows software, so many potential subjects will already be familiar with it. Second, as I can attest personally, for some people the game can be quite addictive, in the sense that once one starts playing, one wants to continue. This suggests an experimental design in which subjects can continue to play solitaire by using psi in a positive manner. Also, because solitaire is a game that can be scored, another sort of motivation can be supplied by offering a prize to the person who achieves the highest score in the experiment. Because subjects' scores cumulate across the number of ga mes played, using psi to play more games also increases the chance of winning the prize.
Because the solitaire game software cannot be accessed by the user, it was necessary to build the psi component into a separate program that was interfaced with computer solitaire. Subjects began by playing a set of four solitaire games. Whether they could move on to another set was influenceable by psi in the following manner. Unknown to the subject, a button press called for by the companion program to change a screen also activated the computer's pseudo-random algorithm so that it generated a number from 1 to 4. This number defined a "key game," and continuation in the experiment depended on subjects' getting a relatively high score in the key game. Thus, subjects could use psi to designate one of the games on which they would obtain a high score as the key game, thereby allowing themselves to continue playing. …