This propositional manifesto is an example which demonstrates how a critique of a propositional manifesto can be created by adding elements to a copy of the manifesto being critiqued, as explained here.
The sample critique can be found here.
The theme of this propositional manifesto is that money is something that makes people happier, and money doesn't cost that much to make, so why don't they make more of it?
Most people wish they had more money, and most people experience an immediate feeling of happiness whenever they discover for some reason that they have acquired some money that they did not expect to receive. Conversely, most people are unhappy when they unexpectedly lose some money.
In most countries, most items of currency cost less to manufacture than the actual value of the currency item. For example, a US $20 note costs much less then 20 dollars to manufacture.
Most governments, especially democratically elected governments, exist to serve the needs of the people that they govern, and one of their most important jobs is to maximise the happiness of their subjects.
If you have read down this far, just remember that this propositional manifesto is an example.
The critique (which perhaps should be taken more seriously than the manifesto itself) can be found here.
On a somewhat serious note, it may be that writing an ironic propositional manifesto is a good way to argue against a point of view that you disagree with, especially if the person arguing for that point of view hasn't yet written their own propositional manifesto for you to critique it.