It is always difficult to determine with precision the date of any particular event in the ancient history of India; and this difficulty is considerably enhanced by the speculations of European Orientalists, whose labours in this direction have but tended to thicken the confusion already existing in popular legends and traditions, which were often altered or modified to suit the necessities of sectarian controversy.  The causes that have produced this result will be fully ascertained on examining the assumptions on which these speculations are based.  The writings of many of these Orientalists are often characterized by an imperfect knowledge of Indian literature, philosophy and religion, and of Hindu traditions, and a contemptuous disregard for the opinions of Hindu writers and pundits.  Very often, facts and dates are taken by these writers from the writings of their predecessors or contemporaries on the assumption that they are correct without any further investigation by themselves.  Even when a writer gives a date with an expression of doubt as to its accuracy, his follower frequently quotes the same date as if it were absolutely correct.  One wrong date is made to depend upon another wrong date, and one bad inference is often deduced from another inference equally unwarranted and illogical.  And consequently, if the correctness of any particular date given by these writers is to be ascertained, the whole structure of Indian Chronology constructed by them will have to be carefully examined.  It will be convenient to enumerate some of the assumptions above referred to before proceeding to examine their opinions concerning the date of Sankaracharya.

I. Many of these writers are not altogether free from the prejudices engendered by the pernicious doctrine, deduced from the Bible, whether rightly or wrongly, that this world is only six thousand years old.  We do not mean to say that any one of these writers would now seriously think of defending the said doctrine.  Nevertheless, it had exercised a considerable influence on the minds of Christian writers when they began to investigate the claims of Asiatic Chronology.  If an antiquity of five or six thousand years is assigned to any particular event connected with the ancient history of Egypt, India or China, it is certain to be rejected at once by these writers without any inquiry whatever regarding the truth of the statement.

II.  They are extremely unwilling to admit that any portion of the Veda can be traced to a period anterior to the date of the Pentateuch, even when the arguments brought forward to establish the priority of the Vedas are such as would be convincing to the mind of an impartial investigator untainted by Christian prejudices.  The maximum limit of Indian antiquity is, therefore, fixed for them by the Old Testament; and it is virtually assumed by them that a period between the date of the Old Testament on the one side, and the present time on the other, should necessarily be assigned to every book in the whole range of Vedic and Sanskrit literature, and to almost every event of Indian history.