“Karate ni sente nashi” (空手に先手なし), typically translated as, “There is no first attack in karate.”
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Gichin Funakoshi made this principle the second of his “Niju Kun” (Twenty Precepts), reminding us that “karate begins and ends with courtesy”.
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Karate and particularly kata, often suffers a bad name for being outdated and unrealistic. In my view, nothing could be further from the truth. When you look closer at the art’s core principles, you will see that those principles are just as relevant today as they were many years ago.
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It is often cited that kata always begin with a “block”, a defensive method. Therefore following the maxim of “there is no first attack in karate”. However, the motions in kata often labelled as “blocks” (uke from ukeru- to receive) don’t work well as blocks. They are often perceived to move firstly in the wrong direction, and are too big and slow. They do, however, work well when used in other ways.
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Therefore to believe that “there is no first attack in karate” as solely a defensive principle, meaning that we shouldn’t attack first, in my view, is incorrect.
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Choki Motobu, in his 1932 publication ‘Watashi no karate-jutsu’ wrote; “There is an expression, ‘karate ni sente nashi’. Apparently some people interpret this literally and often profess that ‘one must not attack first’, but I think that they are seriously mistaken. To be sure, it is certainly not the budo spirit to train for the purpose of striking others without good reason. [..] when an enemy is serious about doing one harm, one must fiercely stand and fight. When one does fight, taking control of the enemy is crucial, and one must take that control with one’s first move. Thus, in a fight one must attack first.”
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“Sen sen no sen” (先々の先) another Japanese maxim, translated as, “beyond the future” or “the future ahead”, meaning to seize the initiative by pre-emption, before your opponent can launch a physical attack.
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Pre-emption, is often the best option to maximize your chances in any self-protection situation. Following ‘karate ni sente nashi’ literally, requires an attacker to first launch a physical attack before responding, which could be highly dangerous, and is often not the best option.
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Kenwa Mabuni wrote; “When faced with someone who disrupts the peace or who will do one harm, one is as a warrior in battle, and so it only stands to reason that one should seize the initiative and pre-empt the enemy’s use of violence. Such action in no way goes against the precept of ‘no first attack’ …the expression ‘karate ni sente nashi’”
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The concept of pre-emption is not only recommended by self-protection instructors but it is also recognized in self-defense law. It was a core aspect of traditional karate found within the writings of a number of famous pioneering masters, who were well-known to have supported the karate maxim, “karate ni sente nashi”. They believed that striking first does not necessarily violate the ‘sente nashi’ principle.
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“Karate ni sente nashi” then, is not so much a guideline of how to apply karate in a fight, but perhaps a guideline of the standard of behavior expected from its practitioners. 
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