Great to hear! Some good texts to consider, which will take you through the end of the main syllabus in an introduction to first-order logic are Chiswell and Hodges and Smith. If you ever get the chance to look back through this material I'd recommend taking a look at Goldfarb, but I don't think that's a great place to start in your situation.
I think Goldfarb is very thorough, although he can get somewhat dense. Then there's Tomassi, who's more conversational/informal (while still going over mostly the same stuff as Goldfarb). The second is probably more beginner friendly, but it's also quite a bit longer. If you know math, I imagine you would get through Goldfarb pretty well though.
This introductory is used in many college courses: Deductive Logic
http://www.amazon.com/Modern-Formal-Logic-Primer-Sentence/dp/0139031707
or
http://www.amazon.com/Deductive-Logic-Warren-Goldfarb/dp/0872206602
both use variations of natural deduction for proof systems. I'd check these out.
Great to hear! Some good texts to consider, which will take you through the end of the main syllabus in an introduction to first-order logic are Chiswell and Hodges and Smith. If you ever get the chance to look back through this material I'd recommend taking a look at Goldfarb, but I don't think that's a great place to start in your situation.
I think Goldfarb is very thorough, although he can get somewhat dense. Then there's Tomassi, who's more conversational/informal (while still going over mostly the same stuff as Goldfarb). The second is probably more beginner friendly, but it's also quite a bit longer. If you know math, I imagine you would get through Goldfarb pretty well though.