Heizenberg's Uncertainty Principle

 Nobel laureate Weinberg (Ref. 7 of the English translation of the original paper by Heisenberg's paper)  has written as follows: ‘If the reader is mystified at what Heisenberg was doing, he or she is not alone. I have tried several times to read the paper that Heisenberg wrote on returning from Heligoland, and, although I think I understand quantum mechanics, I have never understood Heisenberg’s motivations for the mathematical steps in his paper. Theoretical physicists in their most successful work tend to play one of two roles: they are either sages or magicians....It is usually not difficult to understand the papers of sage-physicists, but the papers of magicianphysicists are often incomprehensible. In that sense, Heisenberg’s 1925 paper was pure magic."

So, it is very difficult to understand the Uncertainty principle from original paper. The paper in the above link try to give the method that Heisenberg may have used.