become illusionary, if the existence of PK had to be taken seriously; for no experiment could be relied upon to furnish objective results, since all measurements would become falsified to a greater or lesser degree, according to his PK ability, by the experimenter's wishes." Planer concluded the concept of psychokinesis is absurd and has no scientific basis. Philosopher and physicist Mario Bunge has written that "psychokinesis, or PK, violates the principle that mind cannot act directly on matter. (If it did, no experimenter could trust his readings of measuring instruments.) It also violates the principles of conservation of energy and momentum. The claim that quantum mechanics allows for the possibility of mental power influencing randomizers—an alleged case of micro-PK—is ludicrous since that theory respects the said conservation principles, and it deals exclusively with physical things." The physicist Robert L. Park questioned if mind really could influence matter then it would be easy for parapsychologists to measure such a phenomenon by using the alleged psychokinetic power to deflect a microbalance which would not require any dubious statistics but "the reason, of course, is that the microbalance stubbornly refuses to budge." Park has suggested the reason statistical studies are so popular in parapsychology is because they introduce opportunities for uncertainty and error which are used to support the biases of the experimenter. Park wrote "No proof of psychic phenomena is ever found. In spite of all the tests devised by parapsychologists like Jahn and Radin, and huge amounts of data collected over a period of many years, the results are no more convincing today than when they began their experiments." Pseudoscience Parapsychological theories are viewed as pseudoscientific by the scientific community as they are incompatible with well-established laws of science. As there is no repeatable evidence for psi, the field is often regarded as a pseudoscience. The philosopher Raimo Tuomela summarized why the majority of scientists consider parapsychology to be a pseudoscience in his essay "Science, Protoscience, and Pseudoscience". Parapsychology relies on an ill-defined ontology and typically shuns exact thinking. The hypotheses and theories of parapsychology have not been proven and are in bad shape. Extremely little progress has taken place in parapsychology on the whole and parapsychology conflicts with established science. Parapsychology has poor research problems, being concerned with establishing the existence of its subject matter and having practically no theories to create proper research problems. While in parts of parapsychology