lack of contradiction the qur’an challenges mankind by saying: "do they not then consider the qur’an carefully? had it been from other than allah, they would surely have found therein much contradiction." [4:82] the fact that there are no contradictions in the qur’an, despite being revealed over the twenty-three year period, under different circumstances, addressing different problems, is a clear indication to the sincere and objective reader of its divine origin. the logical conclusion we have established that the qur’an could not have been written by muhammad (peace and blessings be upon him) nor did he learn it from someone else or collect it from other sources. are you, the reader, still in doubt about this? we ask you, if you are still in doubt to then take up the challenge of the qur’an itself and prove it to be false. ponder upon that fact that not one of the legions of brilliant poets that have lived in the past 1,400 years have been able to match the qur’an beauty and eloquence despite repeated challenges from the qur’an to do so. and they never will. why are they not successful? because the qur’an is indeed the word of god and who can compete with god? god has told us in the qur’an that they will never be able to do it. say: "if the mankind and the jinns were together to produce the like of this qur'ân, they could not produce the like thereof, even if they helped one another." [qur’an 17:88] in other words, the qur’an itself has predicted that it will remain unparalleled and unrivaled for all of eternity. the futility of trying to match the qur’an’s brilliance and eloquence has been foretold: and if you are in doubt concerning that which we have sent down (the qur'an) to our slave (muhammad peace be upon him), then produce a surah (chapter) of the like thereof and call your witnesses (supporters and helpers) besides allah, if you are truthful. but if you do not do it, and you can never do it, then fear the fire (hell) whose fuel is men and stones, prepared for the disbelievers. [qur’an 2:23-24] the above is exactly what has occurred! none have been able to meet this challenge to his day and they can not do so. throughout this work, we have asked the sincere reader to ponder. we also stated in the beginning that if we conclude that the qur’an is the word of god, then we must by extension accept the messengership of prophet muhammad (peace and blessing be upon him) the rational criteria is at the sincere reader’s disposal, and one's emotional commitment to religion should be preceded by an intellectual commitment to it. reason, in fact, is our primary means for finding the truth. we can put any religion or system of beliefs to test by examining whether it is rational, universal, applicable at all times, in all places, and by people of all colors and languages, and whether the religion's scripture is free of alteration, internal and external inconsistencies. a scripture is internally inconsistent if it contains discrepancies and contradictions within its text, and externally inconsistent if it contradicts facts (not theories) from science and nature as we know them. for it is impossible that god does not know his creation or that which he creates. our experience tells us that a few minutes of reasoning can usually leave us persuaded in the truth of god's absolute oneness and uniqueness, so what remains to be studied is which religion is truly monotheistic in its nature. one of the major criteria for distinguishing the truth from errors, that we would like to stress, is the authenticity of the religious scripture. we have presented above indisputable proof that the qur’an is the word of god. the reality is that muslims are the only ones who even claim to have an authentic scripture from god, in its original form, of which not a single letter has been changed. most other religions admit that their scriptures are in fact human writings. and if we say that there is a truth and god, we are likely to believe that god wants us to do certain things and abstain from others. if we are of the view that god would not leave us without a reliable revelation, then the mere fact that muslims are the only ones who even claim to have an authentic revelation could attest to the truthfulness of their claim. however, as mentioned earlier, the qur'an invites us to ponder and reason and to accept faith based on knowledge, rather than the blind following of our traditions. as we have quoted throughout this work from the qur’an: "do they not then consider the qur’an carefully? had it been from other than allah, they would surely have found therein much contradiction." [4:82] again we ask the sincere reader to reflect.