Have you always dreamt about learning guitar but you never got round to it? Possibly each time you think about it you probably think that you are too old and you will probably never make it or maybe you already play but you are not serious enough to make a big improvement. If it sounds like you read on;-). I have finished reading a really cool book: Guitar Zero by Gary Marcus. He is a professor of psychology who started learning guitar from the scratch at age of 38 and he wrote a book about it!
below you can read an interview with Gary Marcus:
Check The website of Gary Marcus here: http://garymarcus.com/
You can also check my highlights from this book here: https://kindle.amazon.com/profile/Wimbledon-School-of-Guitar-London-Guitar-Lessons/11058202