Reddit mentions of Introduction to Logic: And to the Methodology of Deductive Sciences (Dover Books on Mathematics)

Add Coq Art: Interactive-Theorem-Proving-Program-Development in this venue. The book in the parent link is new to me but I like what I've seen so far. The Coq Art book is more about learning to use the Gallina langauge and techniques for writing and using tactics. It has a pragmatic feel, which is weird considering its subject is so close to pure theory. In all it makes a fun "lab" workbook for the autodidact and I am still working through it as I find time.

I also liked "Logic and Structure" by Dirk van Dalen because it gets on with symbols quickly but still has enough explaination for a beginner like me to follow.

I usually hate wordy logic books but I am enjoying Tarski's Introduction to Logic because his prose descriptions and explainations thoughtfully explain why instead of how. I have a few high-school/undergrad books that explain the how in boring and long winded prose. Barf. Tarski's Intro to Logic is also expanding my vocabulary. I wish I would have read this one first, followed by Dirk van Valen's, and finally the top one on constructive logic.

Both Quine and Tarski have great introductory texts.

Honestly - through rigor. I would suggest studying logic, some philosophy (this is about the structure of arguments, and deduction in a general sense) and then something applied, like policy analysis or program evaluation. <- those last two are just related to my field so I know about them, plenty of others around.

Some suggested books that could be interesting for you:

Intro to Logic by Tarski

The Practice of Philosophy by Rosenberg

Thank you for Arguing by Heinrichs

Policy Analysis is instructive in that you have to define a problem, define its characteristics, identify the situation it exists in, plot possible solutions (alternatives), and create criteria for selecting the alternative you like most.

Program Evaluation is really just tons of fun and will teach a bunch about how to appraise things. Eval can get pretty muddy into social research but honestly you can skip a lot of that and just learn the principles.

The key to this is that you're either very smart and can learn this stuff through your own brains and force of will, or, more likely, you'll need people to help beat it into you WELCOME TO GRADSCHOOL.

I've found Alfred Tarski's Introduction to Logic: and to the Methodology of Deductive Sciences to be a great primer on sentential (predicate) logic. Tarski was a good jumping off point from mathematics to mathematical logic and analytical philosophy. Discovering this book was a turning point in my life; it galvanized my interest in mathematics and lead me to study the foundations of mathematics and philosophy of language in my free time.

Quine's Methods of Logic and Mathematical Logic (in that order) have been my favorites, and I've heard good things about Tarski's Introducion to Logic: and the the Methodology of Deductive Sciences but have yet to get around to it.

Introduction to Logic: and to the Methodology of Deductive Sciences by Alfred Tarski really helped me understand the key concepts of mathematical logic when I was young. Dover has republished the book and you can find used copies in great shape for $5 USD.

I can recommend two books which I have read recently.

1. An Introduction to Mathematical Logic is more structured and formal description of logic.
   
2. [Introduction to Logic] (http://www.amazon.com/Introduction-Logic-Methodology-Deductive-Mathematics/dp/048628462X/ref=sr_1_7?ie=UTF8&qid=1449702263&sr=8-7&keywords=mathematical+logic) gives more insights and helps to get a big picture of logic.
   I enjoyed both of them a lot and going to read them again.