Life is weird. In 1972 I took a course at the University of Illinois at Chicago and this was the book they used. The course, the professor, and this book changed my life (yes, really). I had been a business major, but I had a lot of elective units to burn. My counselor suggested "Introduction to Formal Logic". I loved it; I felt like I had come home.
Fast forward a year and a half: I'm now a programmer looking for work in Silicon Valley. Because I had been involved with PLATO IV at the U of I, I was using the PLATO terminals at IMSSS (at Stanford) to IM with friends back home (that's right, kids, we had IM in ... 1974). Unbeknownst to me, IMSSS was the personal kingdom of one Dr. Patrick Suppes.
A month later I was hired to work for Computer Curriculum Corporation, Dr. Suppes' company that sold Computer Assisted Instruction systems to schools all over the country. I worked there for 3 years and it was a great experience.
Oh, the book! It's almost 40 years ago, but I still remember the book as presenting ideas -- new to me -- in a clear, almost sparse style. I did not know it at the time, but this is the essential voice of Dr. Suppes. I strongly recommend this book to anyone seeking to understand the logical underpinnings of deduction and argument. I wish I could also give you my prof from those days, but he, like Dr. Suppes, has retired.