Almost any system of core actions will include the parry and the riposte. So what is a parry and why do we make parries? Let’s take the second part of the question first. The purpose of a parry is to score a touch on the opponent. Wait a minute … a parry is a defensive action that blocks the opponent’s attack so that it does not score. Ah, wrong again. A parry is an action that causes the opponent’s attack to fail to land (in the right of way weapons with the right of way) and creates the conditions for the riposte to score. It is the first tempo of your attack executed in the middle of his attack.
Those answers would be considered strange, controversial, and even dead wrong by many fencing masters. Fencing masters tend to traditional understandings of the character of combat. But those understandings can hamper the development of a realistic theory of how to win. Let’s take the example of the parry as something that is solely defensive. We have known since the last decade of the 1300s or the first decade of the 1400s (when Master Johannes Liechtenauer’s zettel teaching the use of the longsword started to be recorded in writing) that the parry as defense does not score hits. Liechtenauer and generations of his disciples said in effect that if all you do is parry you are going to die. Blocking the blade does not hit the opponent. So why do parries? … because they create the conditions that allow you to do an offensive action that will hit – the riposte. With the parry you know (1) where the opponent’s blade is and (2) what line is open, and (3) have your blade in position to strike into the open line with (4) the safety provided either by right of way (foil and sabre) or by your control of his blade by the beat, opposition, or transport (epee).
But that is not the entire picture. There is another type of parry, the parry by distance, that causes the opponent’s attack to fall short, creating the opportunity to riposte. It has become fashionable to deny that there is such a thing as a parry by distance because there is no blade contact. And we insist that you have to have a blade contact parry in order for an offensive action at the end of the parry to be called a riposte. Instead we talk about pulling distance and taking over the attack. Examine these supposedly different actions rationally with the criteria of (1) does it cause the attack to fail to score and (2) does it result in a hit? You will come to the inevitable conclusion that the core purpose of a blade parry and riposte, a distance parry and riposte (being an offensive action after a parry, whether or not blade contact is involved), and a pull and take over are the same.
The parata di misura or parry by distance (or measure) is simply another parry, a staple of traditional Italian fencing theory, inherently no different in purpose or tactical outcome from a nicely executed lifted second in epee, or a ceding parry into fifth in foil, or a low second in sabre. It is a matter of degree of footwork – a longer step back in contrast to the short step back we sometimes take to increase the time to execute a blade parry. If we understand that, we are in better position to think about how to use the parry to hit the opponent. As an aside, there is an unintended consequence – if we understand that, it also makes dealing with the opponent who pulls and then takes over the attack easier (hint: think second intention).
Parries can be executed in two ways, to defend ourselves against an attack or to control the opponent’s tactical concept and blade action to create an opportunity for us to score. Inevitably opponents will attack, and we will have to be able to cause that attack to fail. However, we are in a better position if we can create the conditions that will induce an opponent to attack in a specific way so that we can apply a specific desired parry-riposte combination to hit. The opponent’s blade is your friend, you want to welcome it, momentarily hold onto it, and thank the opponent for it use by hitting him or her. This is the traditional role of invitations and second intentions. This creating predictability in the opponent’s attack is also a role of Harmenberg’s destructive and confusing parries.
So think about the parry as not a passive action, but rather as an aggressive one. This may help you if you do a parry and a riposte as two tempos with a physical or mental pause between the two (even if that pause is in milliseconds), as opposed to a parry-riposte as essentially a one tempo continuous action. It may help you to execute effective active parries, seeking out the opponent’s blade so that you can parry earlier in the attack using the momentum of the attack to guarantee the effectiveness of your riposte. It may increase your comfort in seeing the attack coming at you. But best of all, it will help you increase the offensive mindset of your game.