This generation definition changed by Jehovahs witnesses

Jehovah's Witnesses in "Generation of 1914" doctrinal Crisis: Will the JW transform from Cult to Church in the post-2014 era? June 29, 2011 By john thomas Didymus

Dawson writes with reference to the failure of 1975 date previously set for Armageddon by the leadership of the Jehovah's Witnesses:

Singelenberg’s detailed analysis of the nature and consequences of the 1975 prophetic disconfirmation of the Jehovah’s Witnesses presents an interesting test case of the role of leadership, one that falls between the extremes examined so far. The leaders of the church responded quite strongly, though not too quickly, to the failure of 1975. They chose, however, more or less to repudiate the prophecy, even though they had promoted it. They hid behind the vagueness of the prophecy’s terms of reference, terms that may well have been kept vague as a safe guard against the possibility of failure. This definite yet compromised response prevented a full scale disaster, but it cost the church many members in
the short run.

The Governing body of the Jehovah's Witnesses has for decades taught that the beginning of World War I, in 1914, marked the commencement of Jesus' invisible Parousia in heaven, and that the generation of 1914 which saw the commencement of Jesus' Invisible presence (will not "pass away" (Matthew 24:34) before the occurrence of a catastrophic Armageddon which will destroy all "enemies of Jehovah" (read: all none Jehovah's Witnesses). With repeated attempts at setting the length of a generation having failed, the governing body of the Jehovah's Witnesses (which calls itself the "faithful and discrete slave class"–remnant of the 144,000 described in Revelations 7:2-4) introduced, in 1995, a new doctrine of the length of a generation now termed the "two overlapping generations doctrine."
Recent comments by former Witnesses, on Jehovahs-Witnesses.net , on this new doctrinal innovation by the leadership of the Jehovah's Witnesses, suggests that the group may well have commenced a post-2014 era of transformation from "cult" to mainstream leaning organization in which expectation of doomsday is postponed sufficiently to allow time for the original "generation of 1914" cult belief gradually and quietly dropped and finally openly repudiated.
The governing body of the Jehovah' Witnesses explains its new "overlapping generations" teaching in a study edition of the Watchtower Magazine, April 15th, 2010 (pg. 27-29), as follows:
Although we cannot measure the exact length of “this generation,” we do well to keep in mind several things about the word “generation”: It usually refers to people of varying ages whose lives overlap during a particular time period; it is not excessively long; and it has an end. (Ex. 1:6) How, then, are we to understand Jesus’ words about “this generation”? He evidently meant that the lives of the anointed who were on hand when the sign began to become evident in 1914 would overlap with the lives of other anointed ones who would see the start of the great tribulation.
Leon Festingers et al after conducting what is now widely acknowledged as a classic study of a UFO cult in 1954. He published the result of their study in "When Prophecy Fails." The study noted the tendency of doomsday cults, like the Jehovah's Witnesses, to adjust to failure of prophecy by rationalizing in a manner which makes it unnecessary to give up the basic assumptions and beliefs underlying their world-view. In terms of the theory of cognitive dissonance, Festinger et al, explained that groups generally adjust their beliefs in conformity with their behavior. Thus, the more committed an individual is, in his behavior, to an outcome ( an imminent Armageddon, for instance) the greater the compulsion to reduce the tension created by circumstances which challenges the validity of the belief by adjusting one's set of beliefs.

Jehovah's Witnesses in House-to-House Preaching
The cognitive dissonance theory explains the resilience of groups termed "cults" in the face of a consistent pattern of failed prophecies. Consonance seeking behavior by rationalization would appear most pronounced in doomsday or millenarian cults, and the Jehovah's Witnesses have long been recognized by scholars and experts in the field as the best example in western culture of groups seeking reestablishment of consonance by spiritualizing rationalization of failure of prophecy. The rationalization process is intimately involved in the adaptive changes by which doomsday millenarian "cults" survive, thrive and even transform fringe "cult" identify to mainstream "church" identity in the era of their life histories following failure of cult establishing end-time prophecy.
The best example of a process of spiritualizing rationalization in transition from cult to church in recent American history is provided by the Millerites who, after a series of disappointments culminating in the "great disappointment" of 1844 (with regard to their highly publicized date-setting predictions of the second-coming), managed to adjust their belief systems by spiritualizing the "great disappointment" in their "Investigative Judgment" doctrine, and have survived today in the form of the mainstream Church, The Seventh Day Adventists.
According to Dawson in his, When Prophecy Fails and Faith Persists: A Theoretical Overview, rationalization of failure may sometimes also involve attribution of failure of prophecy to human error, an approach which appears to be the main strategy of the Jehovah's Witnesses governing body in the recent cognitive consonance seeking doctrinal reviews(spiritualizing rationalization having been the basis of establishment of 1914 as date of "invisible coming" or parousia of Christ, following the failure of Armageddon date setting at 1914).
Dawson writes with reference to the failure of 1975 date previously set for Armageddon by the leadership of the Jehovah's Witnesses:
Singelenberg’s detailed analysis of the nature and consequences of the 1975 prophetic disconfirmation of the Jehovah’s Witnesses presents an interesting test case of the role of leadership, one that falls between the extremes examined so far. The leaders of the church responded quite strongly, though not too quickly, to the failure of 1975. They chose, however, more or less to repudiate the prophecy, even though they had promoted it. They hid behind the vagueness of the prophecy’s terms of reference, terms that may well have been kept vague as a safe guard against the possibility of failure. This definite yet compromised response prevented a full scale disaster, but it cost the church many members in
the short run.
In his When Prophecy Fails and Faith Persists, Dawson explains that the survival of a cult, when prophecy fails, may depend on the intensity of dissonance felt in the first place and, secondly, on the ability of the leadership in dissonance management. Dawson suggests that for most cults which survive the failure of prophecy, dissonance may not have been as intense for insiders as perceived by outsiders (religious beliefs being unlike scientific beliefs). Those members for whom dissonance was most intense are those who defect while those who stay form the nucleus of a new "settled" organization which may actually expand proselytizing efforts in period following failure of prophecy and gradually acquire a mainstream status.

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