There have been a number of times in human history when a newly created technology would forever change life thereafter. The knowledge and ability to utilize fire is one such development, the development of agriculture another, and the use of electricity can be seen as a more modern example of this kind of revolutionary leap. It's through these leaps forward in technological prowess that civilization is made possible. I tend to think it's important to also note how technology moves forward due to an ever increasing body of knowledge. For example it's not reasonable to think that the jet plane could have existed before the motor car, or the internet could have existed before the light bulb. So if modern life is the result of thousands of years of human progress then one tool stands out as a truly fundamental pillar of civilization and that is cutting blade. Archaeology claims that as early as 50,000 years ago our ancestors were using flint and obsidian blades. The incredible range of uses a sharp blade provides should be obvious and so it's no mystery why early humans would seek to develop better and better blades. Slowly over many thousands of years flint and obsidian would give way to copper, then to bronze, then to iron, and finally steel and modern alloys were developed. These developments were fundamental to our progress as a species. So much so that we name the some of the epoch's of human history after the technological level of the metallurgy being done at that time such as the Bronze Age, Iron Age etc. The advantage of a cutting blade would have been wholly revolutionary to an early humans and two main types of weapons would be created with these blades that would remain vital to humanity right up until modern times. They are the sword and the spear. Both weapons have been made in numerous styles and sizes throughout history and exist in virtually every society and civilization that has ever existed. Between the two weapons the thing makes the sword unique is that it is better suited to be an individual fighters weapon, whereas the spear is best utilized by groups of solders in rank and file. This has lead the sword to become synonymous with personal power and in the end it became an anchor in our collective unconscious as a symbol of both strength and justice. Truly no other weapon commands such an important place in both history and myth as the sword. From the legends of King Arthur's sword Excalibur to the incomparable Japanese Katana, from the Roman soldier's Gladius to the great sword Andúril in the Lord Of The Rings Trilogy. Swords are everywhere and play a fundamentally important role in both fiction and real life. This is an interesting phenomenon in that despite the glowing high place swords keep in life and ritual/symbolism the job they do is really quite gruesome. It begs the question of how a tool designed to hack people apart came to be a symbol of Justice. Originally I think it was spears that really changed our ancestors lives the most directly. A spear could allow a person to fend off an attacking wild animal and generally gave early humans a huge boost in establishing humanity at the top of the food chain. Swords really are built much more towards human on human violence. They are largely the ultimate individual weapon and as civilization grew so did the concepts of empire and conquest. This meant the idea of self defense took on a newly important role in the life of the average person. Its here that the doubled edged nature of technology presents itself. If someone was viciously attacking me with a bladed weapon then I would definitely prefer to have a similar weapon to use in my defense. If not then I would prioritize taking the attackers weapon away and using it against them if necessary to bring the attack to an end. So the sword can do great harm or it can prevent great harm from being done. But a world without the cutting blade is one where we could not have developed society very far. So this issue cannot be resolved by getting rid of blades. It's for this reason that a good martial arts school will devote some amount of time to training with blades both in the sense of how the blade is used and also how to disarm a bladed attacker. Of all the kinds of weapons that get used in assaults a bladed weapon is the most common. At this time in history such attacks are almost always one kind of knife or another. Anything from a pocket sized switch blade, to a hunting knife, or even a common kitchen knife can be a deadly weapon. However regardless of which one is being used they all must be wielded within limitations of what a human being with two arms and two legs can do with a cutting object. This means if you learn to deal with any kind of knife you will have developed a fighting chance to deal with any other bladed weapon as well. To be sure though any fight with a cutting blade is absolutely deadly serious and should be treated as such. There is an old saying in Japanese Kenjutsu/sword fighting schools that a person going into a sword fight only has a 33.3% chance of surviving. Not good odds and not something to be taken lightly. Much of martial art training is purposefully directed towards absolute worst case scenarios and this is a prime example of that. This means that standing and fighting someone with a blade is the last possible thing one should do. Get away, give them your wallet or whatever else, anything else than can be done to avoid a blade being swung towards you is priority. However that being said if there truly is no other option then one must fight such an assailant in a severe and deadly serious way in their defense. So by now we can see that cutting blades are an intrinsic part of the human world. And since people do not seem likely to stop attacking each other any time soon then it is distinctly advantageous to know how blades are used as weapons and how to defend against such attacks. This truth is exactly the kind of truth that martial arts are built upon. Seeing things as they are and working tirelessly towards the best possible result within the constraints reality presents. It's like the old head on the sand analogy, if your heads in the sand then you have no real chance of surviving a hurricane. However if you face the storm and do what you can to avoid getting killed then you at least have a chance. This is the truth of the blade. Things are as they are, so how are you going to respond, that is what matters. It is a very delicate truth. In the Aizu Clan of Japan from which the Takeda Family and the Daito Ryu comes from there is a old saying that the truth lies on the cutting edge of a blade. This makes the truth a precarious thing that must be treated with delicacy and great care just a real live blade is. If this can be understood then it can finally be understood how the blade can be seen as the perfect embodiment of the truth. Like the truth it cuts deeply and when used carelessly can do great harm but without it the world could not exist as it does. It is for this reason that the way of using a blade has been of enormous value to me. It has given me what I feel is a deep insight into life and so I am honestly grateful to have come to know the cutting blade and because of that to have gotten a glimpse of the truth it reveals. I hope you find the same for yourself someday.
Think of your opponents hands and feet as swords.