A ninja is one who practices ninjutsu
. The existence of the Ninja as being the secret mercenaries that Ads
described is folklore. The problem that surrounds us that Japanese history is word of mouth
a lot of the time. If a Shogun
could convince people he was employing an elite squad of warriors with magical powers, he would. And he certainly wouldn't document the deception for historians to read about later.
The meaning of the symbol pronounced Nin is also often misunderstood. The symbol can be also pronounced shinobi which means "endurance". The word Nin really means to be in control of one's mind and body - and to know one's perception of right and wrong.
Another problem lies in generalising the ninjutsu warriors as one group. Most of the ryu of what is now known as ninjutsu were seperate schools. Both in thought and in fighting technique. There was no "Ninja code of honour" for the ninja belonged to different ryu with different philosophies. It is only recently (since Takamatsu Toshitsugu) that ninjutsu has been grouped together to make one distinct marital art.
Also, the history of the ninja started in 1161 and continues to modern day. That is almost 1,000 years of history to generalise by saying the ninja did this or they did that. For example what did a knight of England do 1,000 years ago? Probably a lot different to what Sir Paul McCartney is doing 1,000 years later. There was probably a time when there was a lot of mercenary espionage ninjas, and these are what we think of when we look back on them (much as we think of knights as being plate mailed horsebacked heroes). When we think of such ninjas we are probaly thinking the secretive Gyokushin Ryu, of which there is still precious little known.
So you see, the history of the Ninja is written in hindsight and is based on scant historical records, folktales and spook stories. The Japanese are sometimes confused by the West's obsession with history. The term "History is written by the victors" is very true of Japan's history. Since espionage was an art form for much of Japan's past, we know that they probably would value that "information is power". As much, they wouldn't write how they defeated their enemies down, so that somebody could use those same techniques against them later.
The title of Samurai is not mutually exclusive to the title of ninja either. Samurai often practiced (what is now known as) ninjutsu, and indeed some found their own schools. In fact, Daisuke Nishina, the founder of the first Ryu, Togakure Ryu was from a highly ranked Samurai Family. His father was Samurai for Daimyo Yoshinaka Minamoto, the cousin of the first Shogun of Japan.
A lot has been written of the ninja which is plain wrong. Some ninja may have been ruthless killers dressed in black who specialised in infiltration and had a strict code of honour and fought to the death. But not all. Some schools loathed violence, and others abhored death.
NINJUTSU AND TRADITION By Sensei Masaaki Hatsumi
History of Bushido, by Paul Richardson