Gichin Funakoshi is considered the father of modern karate-do.
He summed up his views of karate with 20 principles:
1 Never forget that karate begins and ends with respect.
2 There is no first attack in karate.
3 Karate fosters righteousness.
4 First know yourself and then know others.
5 Rather than physical technique, mental technique.
6 Let your mind roam freely.
7 Inattention and neglect causes misfortune.
8 Never think that karate is practiced only in the dojo.
9 Karate is a life-long pursuit.
10 Everything you encounter is an aspect of karate: find the marvelous truth there.
11 Karate is like boiling water: if you do not keep the flame high, it turns tepid.
12 Do not think about winning; think about not losing.
13 Respond in accordance to your opponent.
14 Wage the battle with natural strategy.
15 Regard your hands and feet as sharp swords.
16 Step out the door and you face 10,000 foes.
17 Learn various stances as a beginner but then rely on a natural posture.
18 The kata must always be practiced correctly: real combat is another matter.
19 Never forget your own strengths and weakness, the limitations of your body, and the relative quality of your techniques.
20 Continuously polish your mind.