Learning Bach Inventions

[faa2010]

One of my goals right now is to learn how to play at least one of Bach's Symphonies (also known as Three-Part Inventions), and in order to do that, I suppose, is to learn and practice first the Two-Part Inventions.

What is the "correct" way and order to learn Bach's inventions?
How will I know that I am ready for learning the next one?

[asiantraveller101]

What is the "correct" way and order to learn Bach's inventions?
How will I know that I am ready for learning the next one?

There is no correct or wrong way, nor an order, to learn the inventions. Yes, to be able to play the three-part sinfonia, one would have to be comfortable with the 2-part. Usually one begins the simpler 2-part, for example the C maj, D min, D maj, or B-flat maj, and work through a few of them. One does not have to learn every one of them. The B min sinfonia is probably one of the easiest one to try. You may even want to try that one.
To be ready or not for the next, is a goal you set for yourself. (Or a goal set by your teacher). Are you going to learn them so that you can read and play contrapuntally? learn to perform those pieces? able to memorize them? It is really a goal you set for yourself.
My suggestion is to learn to memorize at least one/few of them. Memorizing contrapuntal work is different from memorizing a homophonic piece. It will definitely help you to memorize anything later with multiple lines. 
Good luck, and hopefully you will enjoy them.

[scott13]

Learn 3-4 Preludes and Fugues from Well Tempered Clavier and nothing from the Baroque period will give you grief again, as the technique you develop playing 4 part Fugues is amazing.

I really wouldn't advise working on the inventions (2 or 3 part) unless you couldn't handle even the easier P & F from book one, such as # 1 in C Major, and the E minor one (unsure of number)

[raphaelinparis]

hi
if you are a beginner or a fresh intermediate level player, then learning 2-parts Bach inventions should dramatically enhance your playing. Today I can say with confidence that this was a quantum leap for me, because there was clearly a big difference in my playing between "before" and "after" I learned Bach inventions.
Surprisingly, I have learned only inventions #1 and #8 and then moved on, and I don't think you need to learn more than 2 or 3 2-parts inventions: as soon as your brain gets the "trick", the job is done, and you can probably move on and learn more "challenging" music. Now I am using 2-parts inventions mainly for sight-reading.
Fugues from WTC are way more difficult, as you will understand quickly if you give it a try.
ps: my mother tongue is French, so I am sorry for the mistakes / typos (you are lucky, at least you don't hear my terrible accent)

[gore234]

I learned to play five of the 2-part inventions so far and my piano playing improved alot.  I learned numbers 13,14,8,1,and 4 in that order and I think those are the easier ones in my opinion.