I really like the tone of this book and absolutely love the historical motivations provided by the author for all of the topics presented. In my humble opinion though, the book lacks sufficient rigor and detail to really serve as a complete introduction to analysis. The proofs lack sufficient detail and many of the theorems still rely too heavily on an intuitive understanding rather than a rigorous axiomatic treatment. Although completely lacking the excellent motivation for the theorems provided by Abbot I would highly recommend Apostol's Mathematical Analysis (considered a classic by many) as the ideal introduction to the "heavy" analytic treatment of calculus. The absolute perfect combination would be both books together (which is what I ultimately used to understand the basics of analysis).<br><br>I don't disagree with the other reviews on how excellent the book is but I don't know that it can really stand alone. For instance, it would be a considerable leap for someone to read this book and then jump in "feet first" into Rubin's Real and Complex Analysis, which someone should be able to do after completing an intro to analysis textbook.