If you could pick any book to be the Textbook of your Martial Art, or your training philosophies, what would it be and why?

The Pinnacle of Okinawan Karate by Robert Trias.

This is what we study, and it's got the basic interpretations and instructions for everything in our system.

It also includes hints for alternative interpretations, though sometimes you have to look carefully.

Great question.

Given what's out there, I'd have to say Living the Martial Way, but Forrest Morgan. You just have to rip out all his references to kata .

I would have to say:

The New History of Shorin-Ryu Matsumura Seito...and...The Spirit of Okinawan Karate Throughout the World, both by Hanshi Fusei Kise.

Both are in great detail about the history of Karate, Hohan Soken, never before seen photos and even documents in the past about the origins of Shorin Ryu. It's really something special.

From the details:

In 2001 the Government of Japan gave there Seal of Approval to the accuracy of Master Kise's book. They have stated that he (Grand Master Kise ) is the sole true heir to Matsumora Orthodox Karate, being passed down to him from Hohan Sensei. This has been entered into the official Government Archives. This means there can be no more disputing the Lineage of Matsumora Orthodox Karate.

Well Gen. Choi's Encylopedia of Taekwon-Do is actually our "official" textbook for the style. I've not really had much of a look through the 15 vol. set but I have a copy of the condensed version and it contains detailed info on pretty much everything you'd need to know for the style.

The Art of War by Sun Tzu. Its principles can be applied to many things in life. Especially the martial arts. Large scale tactics and trickery can be scaled down to one on one confrontations. It's a very complete guide for strategy.

Yes, This is a great question!

The Mas Oyama 3 book series "What Is Karate?", "This Is Karate", and "Advanced Karate".

Why these books as per the OP?

These books are very similar to Shindokan Karate-Do as it was founded by Soke Fuyuhiko Saitou Sensei. Simplistically as I can put it...Shindokan Karate-Do is an extremely demanding full-contact Karate from Okinawa that utilizes full power kicking, punching and striking techniques during sparring matches and training sessions. Tuite is at the most absolute core of Shindokan!

I think if I had to pick of the books that I have read this far, for my outlook on TKD, I would have to go with Stuart Anslow's Ch'ang Hon Taekwon-do Hae Sul. I think that his approach to TKD makes a more well-rounded TKD exponent, especially in presenting the self-defense aspects of the TKD as a whole, and the forms in particular.