Power required and TAS
Both examples of static equilibrium - no net external force on either car, body or ground and no motion. Propulsion is different, there is a net external force causing motion of one body and therefore by conservation law there has to be an equal and opposite change of momentum on another.
You appear to be arguing that if a body is in a state of equilibrium there can be no propulsive force acting upon it. Might I suggest that you look at an aircraft in straight and level flight at constant speed.
Lift = Weight That is why the flight is level.
Forces to the left = force to the right That is why it flies straight.
Thrust = drag. That is why the speed is constant.
The aircraft is in equilibrium but it has a propulsive force (thrust) to maintain this condition.
Stiffness cannot replace the momentum change. Something with mass has to be accelerated.
From these examples you should by now have recognised the fact that a propulsive force can sometimes be generated without accelerating anything.
According to Aerodynamics for Naval Aviators: “the force of thrust results from the acceleration provided to the mass of working fluid”.
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Keith Williams,
An aircraft in unaccelerated flight is not an example of static equilibrium.. The forces on the airframe may be in equilibrium but the thrust results from a momentum change of the jetwash and the drag results from a momentum change of the slipstream. Your example of standing on the ground is static equilibrium – no net force on either body or ground, nothing is moving and there is no momentum change.
You can have a force and counter force without any change of momentum. That would be static equilibrium but it is not propulsion. There is no such thing as a propulsive force that does not involve a change of momentum. It is not always immediately apparent where the change of momentum is taking place but it is always there.
The conservation laws are the most fundamental principle in mechanics and there is no example of them ever having been broken. Your own pet hypotheses are not consistent with them and are therefore incorrect.
You appear to be arguing that if a body is in a state of equilibrium there can be no propulsive force acting upon it. Might I suggest that you look at an aircraft in straight and level flight at constant speed.
I have given you several examples where a Newton 3 force is being generated without anything being accelerated. Some of these examples were static, but at least one was not. Two identical cars driving at the same speed, in opposite directions on the same stretch of road. Because they are exerting equal force on the road, but in opposite directions they cannot both be accelerating the road backwards, in fact neither of them is doing so. But both cars are generating a propulsive force. This is only possible because the road is stiff enough to resist the forces being applied to it. In this example the mass of the road is irrelevant.
From these examples you should by now have recognised the fact that a propulsive force can sometimes be generated without accelerating anything.
From these examples you should by now have recognised the fact that a propulsive force can sometimes be generated without accelerating anything.
The conservation laws are the most fundamental principle in mechanics and there is no example of them ever having been broken. Your own pet hypotheses are not consistent with them and are therefore incorrect.
You can have a force and counter force without any change of momentum. That would be static equilibrium but it is not propulsion. There is no such thing as a propulsive force that does not involve a change of momentum.
The conservation laws are the most fundamental principle in mechanics and there is no example of them ever having been broken. Your own pet hypotheses are not consistent with them and are therefore incorrect.
The conservation laws are the most fundamental principle in mechanics and there is no example of them ever having been broken. Your own pet hypotheses are not consistent with them and are therefore incorrect.
Phase 1
They are tied together by a rope, standing back to back with their engines running, gears engaged and clutch pedal released. Their wheels are exerting a rearward force on the road, which in turn is exerting a forward force on the cars. These forward forces are balanced by equal and opposite forces exerted by the tension in the rope. Both cars and the road are stationary, so the total momentum of the system (2 cars plus road) is zero.
Phase 2
We now cut the rope and the cars accelerate away in opposite directions. The rearward forces exerted on the road by the two cars are equal and opposite so the road is not being accelerated and is not moving, so its momentum is zero. Although the velocity of the two cars is increasing, they are moving in opposite directions at the same speed, so their total momentum is zero. So the total momentum of the system is still zero. The cars are both accelerating so they must be experiencing propulsive forces, but the total momentum is not changing.
Phase 3
After a few seconds the increasing aerodynamic drag and rolling resistance acting on each car will equal the propulsive force being exerted by the road, so their speed will become constant. As before, the road is not moving or accelerating and not moving so its total momentum is still zero. The two cars are not accelerating, but are moving in opposite directions at a common speed, so their total momentum zero. But the fact that the cars are maintaining their speed while pushing against drag and rolling resistance means that they must be experiencing propulsive forces.
The total momentum of the system has remained constant throughout the entire sequence, so the law of conservation of momentum has not been violated.
The only objects which experience accelerations are the cars (during the second phase), But nothing at all is accelerating during the third phase. But in the second and third phases both cars are experiencing propulsive forces.
It is entirely possible that I have overlooked something in this analysis, and if you can find it and point it out to me I would be grateful
The fundamental argument in this thread is whether the thrust for an aircraft is produced by the rearward force we exert on the air passing through our propulsion systems, or by the rearward acceleration of that air.
If we were asked how our propulsion systems create thrust we could say:
1. By exerting a rearward force on the air passing through them, thereby causing this air to exert a forward acting force in accordance with Newton’s Third law.
Or:
2. We accelerate air rearwards, thereby causing this air to exert a forward acting force in accordance with Newton’s Third law.
Both answers sound reasonable, so we need to ask a second question to decide which is the more valid.
One such second question might be “How do we accelerate the air rearwards?” The answer to this question is “By exerting a rearward force upon it”, which is of course our first answer. We can say that we accelerate the air rearwards by exerting a rearward force on it, but we cannot say that we exert a rearward force on the air by accelerating it rearwards.
The rearward acceleration of air in aircraft propulsion systems is an inevitable, but wasteful consequence of the process by which we generate thrust. Over the years increasingly high by-pass ratios and ever larger fans have been introduced in jet engines in order to reduce the acceleration of the air passing through them. If the rearward acceleration were the hero in all of this we would not by trying to reduce it.
Your own pet hypotheses are not consistent with them and are therefore incorrect.
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The only objects which experience accelerations are the cars (during the second phase), But nothing at all is accelerating during the third phase. But in the second and third phases both cars are experiencing propulsive forces.
It is entirely possible that I have overlooked something in this analysis, and if you can find it and point it out to me I would be grateful
It is entirely possible that I have overlooked something in this analysis, and if you can find it and point it out to me I would be grateful
F = m.a = mΔv/t = rate of change of momentum
No, I do not think that is a valid explanation.
All you have really done is to select a smaller system ( 1 car, the air around it and the road/earth beneath it). But you have ignored the rest of the wider system.
In reality there will be no net torque on the Earth because the torque applied by car 1 is equal and opposite to that applied by car 2. One of the conditions required when applying the law of conservation of momentum is that the system must be an isolated system. In your explanation you have ignored the fact that your smaller system is connected to the other car via the road. And these exert a force on your smaller system.
Perhaps a more valid explanation of the conundrum is that if we consider the whole system (2 cars, the road and the air around them), no overall propulsive force will be produced, because the propulsive force exerted on car 1 will be equal and opposite to that on car 2. This does not mean that the individual cars are not generating propulsive forces, they are doing so. But (and this is a very important but) they are not accelerating anything rearwards. And because they are not accelerating anything rearwards, they are not throwing away energy, so their propulsive efficiency is much higher than that for an aircraft in flight with a conventional propulsion system (prop or jet engine).
All you have really done is to select a smaller system ( 1 car, the air around it and the road/earth beneath it). But you have ignored the rest of the wider system.
In reality there will be no net torque on the Earth because the torque applied by car 1 is equal and opposite to that applied by car 2. One of the conditions required when applying the law of conservation of momentum is that the system must be an isolated system. In your explanation you have ignored the fact that your smaller system is connected to the other car via the road. And these exert a force on your smaller system.
Perhaps a more valid explanation of the conundrum is that if we consider the whole system (2 cars, the road and the air around them), no overall propulsive force will be produced, because the propulsive force exerted on car 1 will be equal and opposite to that on car 2. This does not mean that the individual cars are not generating propulsive forces, they are doing so. But (and this is a very important but) they are not accelerating anything rearwards. And because they are not accelerating anything rearwards, they are not throwing away energy, so their propulsive efficiency is much higher than that for an aircraft in flight with a conventional propulsion system (prop or jet engine).
Last edited by keith williams; 10th Jan 2017 at 11:25.
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Keith Williams,
Well, it was I who pointed out in my first reply to your 'cars pointing in opposite direction' scenario that there was no net torque - and therefore it would not, as you put it, test the argument.
And you did overlook the acceleration of the air in the slipstreams that results in drag and is where most of the engine power is going. But the point you are avoiding is this; if there doesn't just happen to be a second car producing precisely equal and opposite torque to the first car there is a net torque on the Earth. Hence this:
...is wrong.
I am not being obtuse here, I see the argument you are trying to make but it is a fallacy. Stiffness cannot resist the change in angular momentum, there has to be an equal and opposite change of momentum. You keep inventing scenarios with multiple cars and ropes where the net torque on the Earth is zero but the fact remains that in your original example of a single car there is a net torque, and the only thing that resists is the Earth's huge moment of inertia. The equation is simply:
τ = Ι α .....or the linear equivalent, F = m a
If you have an equation for 'resistance to acceleration' as a function of “stiffness” please go ahead and share it.
In reality there will be no net torque on the Earth because the torque applied by car 1 is equal and opposite to that applied by car 2
nothing at all is accelerating during the third phase...But the fact that the cars are maintaining their speed while pushing against drag and rolling resistance means that they must be experiencing propulsive forces...It is entirely possible that I have overlooked something in this analysis, and if you can find it and point it out to me I would be grateful
You are driving down a motorway at 70 mph...because the road is stiff enough to resist the forces involved, it does not experience a rearward acceleration.
I am not being obtuse here, I see the argument you are trying to make but it is a fallacy. Stiffness cannot resist the change in angular momentum, there has to be an equal and opposite change of momentum. You keep inventing scenarios with multiple cars and ropes where the net torque on the Earth is zero but the fact remains that in your original example of a single car there is a net torque, and the only thing that resists is the Earth's huge moment of inertia. The equation is simply:
τ = Ι α .....or the linear equivalent, F = m a
If you have an equation for 'resistance to acceleration' as a function of “stiffness” please go ahead and share it.
Last edited by oggers; 12th Jan 2017 at 08:22.
But the point you are avoiding is this; if there doesn't just happen to be a second car producing precisely equal and opposite torque to the first car there is a net torque on the Earth.
And the point which you are avoiding is the fact that in the real world there just happens to be millions of cars moving over the surface of the Earth at any one point in time. It is true to say that each of these cars exerts a torque on the Earth, but it is not true to say that each of these torques produces an acceleration. There is only one Earth and it is sufficiently stiff to resist these forces, so it cannot be experiencing millions of individual accelerations simultaneously. If the Earth experiences any acceleration at all it will be the result of the vector sum of all of these individual torques. And it is highly unlikely that this net torque will produce an acceleration that happens to be proportional to the torque exerted by any individual car.
The millions of individual cars are separate bodies, so we must consider their propulsive forces individually. So in reality we have millions of individual cars generating millions of individual propulsive forces, with only a single net torque and acceleration of the Earth. And that net torque and acceleration are not what the laws of motion would predict for any individual car.
You have repeatedly argued that the stiffness of the material is irrelevant. Well if the Earth were insufficiently stiff to resist the millions of competing torques being applied by the millions of cars, the surface would be a swirling mass of debris moving in all directions. It is not. Why Not? Because it is stiff enough to resist these forces.
You have repeatedly stated various equations of motion, in what appears to be an attempt to convince me that they are true. You are wasting your time because I already know that they are true. I studied them in secondary school and again in various career courses, and spent several years teaching them to university students. But what you are unable or unwilling to do is to look beyond these equations and see what actually happens in the real world.
To see what I mean let’s go back to your hamster wheel. This time we will insert two identical hamsters and have them run in opposite directions. The torque reaction exerted on the wheel by hamster A is equal and opposite to that exerted by hamster B. This means that the two torques cancel out to zero and the wheel remains stationary. Instead, the two hamster run in vertical loops, one clockwise and the other anticlockwise, within the cage. Each of the hamsters is generating a propulsive force but there is no acceleration of the cage. This does not mean that the laws of motion are incorrect. It simply means that by putting two sets of the equations back-to-back, the predicted accelerations cancel to zero.
You keep inventing scenarios with multiple cars and ropes where the net torque on the Earth is zero but the fact remains that in your original example of a single car there is a net torque, and the only thing that resists is the Earth's huge moment of inertia. The equation is simply:
τ = Ι α .....or the linear equivalent, F = m a
τ = Ι α .....or the linear equivalent, F = m a
1. In reality there are millions of cars moving over the Earth, so the actual results are
not what is predicted for a single car.
2. I already know and understand the equations, so you will achieve nothing by
repeatedly stating them
If you have an equation for 'resistance to acceleration' as a function of “stiffness” please go ahead and share it.
I have never argued that there is a direct relationship between the stiffness of a material and the acceleration produced. What I have done is to cite several examples of situations in which the stiffness of the intervening material enables the forces exerted by one body to be felt by another, in a way which alters the overall outcome. But to understand this you really must look beyond the equations and see what actually happens in the real world.
Life is not an equation, it is much messier than that.
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Keith Williams
This is what you argued in your own words:
There is no conundrum. F = m.a covers it succinctly. You have confused yourself with this stiffness idea. Stiffness is irrelevant, it is for structures and springs. Mass is the measure of inertia.
As anticipated, you don't have an equation for your "road is stiff enough to prevent it from being accelerated" concept because it is not part of any scientific theory. The job of scientists and engineers is not to marvel at the messiness of life but to unravel its mysteries and reduce them to their component parts.
I have never argued that there is a direct relationship between the stiffness of a material and the acceleration produced.
This is what you argued in your own words:
The point which I am arguing is that the thrust in our car or aircraft or whatever, is not generated by the rearward acceleration of whatever we may be pushing against
If you have a problem with the idea that the acceleration of the gas does not actually produce the thrust let’s look at a slightly different scenario. You are driving down a motorway at 70 mph...your propulsive efficiency is 100%. But this is only possible because the material on which you are exerting your rearward force (the road) is stiff enough to prevent it form being accelerated
Now getting back to our aircraft sitting on the runway, if we release the brakes the aircraft will start to accelerate forward. So our propulsive efficiency is gradually increasing. This process will continue after lift-off. But we will never get to 100% because the exhaust gas is not sufficiently stiff to resist being accelerated rearwards.
If you have a problem with the idea that the acceleration of the gas does not actually produce the thrust let’s look at a slightly different scenario. You are driving down a motorway at 70 mph...your propulsive efficiency is 100%. But this is only possible because the material on which you are exerting your rearward force (the road) is stiff enough to prevent it form being accelerated
Now getting back to our aircraft sitting on the runway, if we release the brakes the aircraft will start to accelerate forward. So our propulsive efficiency is gradually increasing. This process will continue after lift-off. But we will never get to 100% because the exhaust gas is not sufficiently stiff to resist being accelerated rearwards.
Perhaps a more valid explanation of the conundrum...
Life is not an equation, it is much messier than that.
The words which you have quoted do not argue that there is a direct relationship between stiffness and acceleration.
Our aircraft propulsion systems exert rearward forces on the air in their immediate vicinity, but not in the wider atmosphere. If we were to gradually increase the stiffness of the air, this would cause a gradual increase in the volume and mass of the air affected. This in turn would reduce the rearward acceleration, but would not reduce the propulsive force. If we continued to increase the stiffness we would eventually reach a point at which the entire atmosphere would be affected. The rearward acceleration of the air would be vanishing small, but again the propulsive force would not have changed. If we now make the air even stiffer, the entire atmosphere and Earth would be affected. Once again the acceleration would be smaller but the propulsive force would be unchanged. If we now increase the stiffness even more, there would be no change in acceleration or propulsive force. So although we can influence the acceleration by changing the stiffness of the air, there is not a direct quantifiable ratio between stiffness and acceleration.
In an earlier post you said:
But my examples of the two cars and the two hamsters illustrate the fact that it is entirely possible to create a propulsive force without any change in momentum.
You are correct, but it also not the job of scientists and engineers to carry out experiments then simply dismiss unwanted results with comments such as
, which you used earlier.
The job of scientists is to compose hypotheses, carry out experiments to prove or disprove them, analyse the results of these experiments then amend their hypotheses accordingly. Your approach in this thread has been to ignore results which you do not like and then simply restate the laws of motion.
The job of engineers is to look at how the world really works then use these observations to devise solutions to problems. An example of this is contra-rotating propellers as used in the Fairey Gannet aircraft. The Gannet was powered by a Twin Mamba turbine engine, which produced a great deal of power. If this power were to be fed into a single propeller the torque reaction would cause the fuselage to rotate very rapidly in the opposite direction to the propeller. This would make the aircraft uncontrollable and would probably tear it apart.
To prevent this the designers used two propellers spinning in opposite directions, but on the same axis of rotation. The front propeller was driven by a drive shaft which passed through the centre of rear propeller drive shaft. In this way the torque reactions of the two propeller were set against each other within the gearbox, causing them to be cancel each other out, so no torque was applied to the fuselage.
For all of this to be possible it was necessary for the gearbox structure to be sufficiently stiff to resist the two opposing torque reactions without being destroyed. Had the designers simply looked at the equations of motion and not beyond them, they would simply have said “we’re stuffed”, and gone home.
Our aircraft propulsion systems exert rearward forces on the air in their immediate vicinity, but not in the wider atmosphere. If we were to gradually increase the stiffness of the air, this would cause a gradual increase in the volume and mass of the air affected. This in turn would reduce the rearward acceleration, but would not reduce the propulsive force. If we continued to increase the stiffness we would eventually reach a point at which the entire atmosphere would be affected. The rearward acceleration of the air would be vanishing small, but again the propulsive force would not have changed. If we now make the air even stiffer, the entire atmosphere and Earth would be affected. Once again the acceleration would be smaller but the propulsive force would be unchanged. If we now increase the stiffness even more, there would be no change in acceleration or propulsive force. So although we can influence the acceleration by changing the stiffness of the air, there is not a direct quantifiable ratio between stiffness and acceleration.
In an earlier post you said:
There is no such thing as a propulsive force that does not involve a change of momentum.
The job of scientists and engineers is not to marvel at the messiness of life but to unravel its mysteries and reduce them to their component parts.
“If there doesn't just happen to be a second car”
The job of scientists is to compose hypotheses, carry out experiments to prove or disprove them, analyse the results of these experiments then amend their hypotheses accordingly. Your approach in this thread has been to ignore results which you do not like and then simply restate the laws of motion.
The job of engineers is to look at how the world really works then use these observations to devise solutions to problems. An example of this is contra-rotating propellers as used in the Fairey Gannet aircraft. The Gannet was powered by a Twin Mamba turbine engine, which produced a great deal of power. If this power were to be fed into a single propeller the torque reaction would cause the fuselage to rotate very rapidly in the opposite direction to the propeller. This would make the aircraft uncontrollable and would probably tear it apart.
To prevent this the designers used two propellers spinning in opposite directions, but on the same axis of rotation. The front propeller was driven by a drive shaft which passed through the centre of rear propeller drive shaft. In this way the torque reactions of the two propeller were set against each other within the gearbox, causing them to be cancel each other out, so no torque was applied to the fuselage.
For all of this to be possible it was necessary for the gearbox structure to be sufficiently stiff to resist the two opposing torque reactions without being destroyed. Had the designers simply looked at the equations of motion and not beyond them, they would simply have said “we’re stuffed”, and gone home.
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Keith Williams,
Hmm. Having started from the position:
of late you have said:
And now:
Now I said many posts back; "stiffness of the road is irrelevant except insofar as it transfers force to something with more inertia. Stiffness is for structures. In terms of propulsive efficiency it is nothing more than a distraction." Having spent literally thousands of words arguing you are clearly coming round to what I managed to say with about 30 words in my second post.
Hmm. Having started from the position:
The important thing to note in all of this is the fact that the thrust was not actually produced by the acceleration of the exhaust gas. It happens because the air is not sufficiently stiff...
...the road is stiff enough to prevent it form being accelerated [whilst] the exhaust gas is not sufficiently stiff to resist being accelerated
...the road is stiff enough to prevent it form being accelerated [whilst] the exhaust gas is not sufficiently stiff to resist being accelerated
I have never argued that there is a direct relationship between the stiffness of a material and the acceleration produced
[blah blah Fairey Gannet blah]... For all of this to be possible it was necessary for the gearbox structure to be sufficiently stiff to resist the two opposing torque reactions without being destroyed. Had the designers simply looked at the equations of motion and not beyond them, they would simply have said “we’re stuffed”, and gone home.
Oggers.
In Post 16 you said:
In post 17 I replied saying:
In post 20 you then continued to attempt to convince me of something to which I had already agreed by saying:
This response typifies the approach which you have taken throughout this thread. When faced with comments with which you disagree you ignore them and simply restate the laws of motion.
Your characterization of my comments as [blah blah Fairey Gannet blah] clearly illustrates the fact that you have no intention whatsoever of considering any opinion other than your own. This makes further discussion pointless, so I will make no further comment.
In Post 16 you said:
It is the mass of the jetwash/propwash/propellant that is the measure of its inertia, not “stiffness”.
In post 17 I replied saying:
You are correct in saying that the mass is the measure of its inertia. We only need to look at Newton’s Second Law equation F = MA to see that.
The stiffness of the road is irrelevant except insofar as it transfers force to something with more inertia. Stiffness is for springs and structures. In terms of propulsive efficiency it is nothing more than a distraction. The important metric is mass - it is one of the 3 basic quantities of mechanics. Stiffness isn't. A kilo of spuds accelerated by a metre/sec² will give you the same reaction as a kilo of air.
Your characterization of my comments as [blah blah Fairey Gannet blah] clearly illustrates the fact that you have no intention whatsoever of considering any opinion other than your own. This makes further discussion pointless, so I will make no further comment.
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Keith Williams
The key point which you have never conceded is this is wrong:
F = m.a. For any given thrust, the acceleration of the exhaust gas varies directly as the inverse of its mass. Stiffness does not come into it.
...”agreed” except the very next word was "But...":
The point of the hamster wheel analogy is that you can see it spin because the moment of inertia is very small compared to the Earth. Your response is proof (in the colloquial sense) that you didn't take the point, even though you now claim to have agreed – in which case the thousands of words you have written seem unnecessary.
I disagreed and made counter points. But it's true there was quite a lot to ignore too, some rambling strawmen plus a few errors I didn't bother with. If there's something in particular you want me to answer feel free. I have some more points I want to make anyway, your withdrawal won't change that. After all, as you wrote: "every day should be a day in school, so please go for it". 
The key point which you have never conceded is this is wrong:
we will never get to 100% because the exhaust gas is not sufficiently stiff to resist being accelerated rearwards.
In post 17 I replied saying:
In post 20 you then continued to attempt to convince me of something to which I had already agreed
Quote:
You are correct in saying that the mass is the measure of its inertia. We only need to look at Newton’s Second Law equation F = MA to see that.
You are correct in saying that the mass is the measure of its inertia. We only need to look at Newton’s Second Law equation F = MA to see that.
You are correct in saying that the mass is the measure of its inertia. We only need to look at Newton’s Second Law equation F = MA to see that. But Newton assumed that the bodies in question were free to move. And if for example, one of the bodies were moving around a pivot such as your hamster wheel, then the stiffness of the bearing would also affect the outcome.
Let’s imagine that we took your hamster wheel and added an adjustable friction brake to the pivot. With the brake fully off the hamster would accelerate the wheel up to some given speed and then maintain this speed for as long as it kept running. But if we gradually tight the friction brake while the hamster continued to run, the wheel would gradually decrease. At some point the friction would be sufficient to stop the wheel, and if the hamster kept running it would follow a vertical looped path inside the wheel. So although we did not ever change the mass of the hamster or the mass of the wheel we have completely changed the outcomes. In order to determine which situation (wheel spinning / hamster stationary or Wheel stationary / Hamster spinning) gave the better propulsion efficiency, we would need to know what the hamster was trying to achieve. And as neither of us speak hamster we can never know that.
Let’s imagine that we took your hamster wheel and added an adjustable friction brake to the pivot. With the brake fully off the hamster would accelerate the wheel up to some given speed and then maintain this speed for as long as it kept running. But if we gradually tight the friction brake while the hamster continued to run, the wheel would gradually decrease. At some point the friction would be sufficient to stop the wheel, and if the hamster kept running it would follow a vertical looped path inside the wheel. So although we did not ever change the mass of the hamster or the mass of the wheel we have completely changed the outcomes. In order to determine which situation (wheel spinning / hamster stationary or Wheel stationary / Hamster spinning) gave the better propulsion efficiency, we would need to know what the hamster was trying to achieve. And as neither of us speak hamster we can never know that.
This response typifies the approach which you have taken throughout this thread. When faced with comments with which you disagree you ignore them and simply restate the laws of motion.
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Keith Williams,
Subjective. Maybe you could explain what happened to the flippant list of silly quotes from post 21, that only disappeared after you decided to get all sniffy about tone?
Your characterization of my comments as [blah blah Fairey Gannet blah] clearly illustrates the fact that you have no intention whatsoever of considering any opinion other than your own. This makes further discussion pointless, so I will make no further comment.
