There are intersecting supply and demand curves. A tax is levied on suppliers. Say the tax is a fixed tax (for example, VAT) and not an ad valorem tax.
Why can we not just move along the demand curve by the value of the tax (as producers just increase the price by the value of the tax)? So for any given point on the demand curve, just increase the price by the given value of the tax and that is the new demand - why does it not work like this?
Whilst I agree a parallel shift of the supply curve by the value of the tax makes sense I do not understand where is the flaw in the earlier method?