From an Economist point of view (this is just my second year), taxes will most of the time negatively affect society in a 'free' market. Why? Because they directly affect production (Quantity) and Price. Every time a company is taxed, it will reduce the amount of goods produced and make the price higher to 'cover' the loss tax generates. This loss from both the consumer (less possibility of buying stuff) and the producer (less production) is often called 'dead weight loss' or 'allocative inefficiency'. Let me use an example:
[Image: http://d.imagehost.org/0090/tax.png]
Under normal circumstances, the optimal price of an MP3 player would be $200, and the amount produced 5k, for both producers and consumers be 'okay'. (For the moment ignore the 'S+Tax' line)
- Consumer surplus is the amount of money consumers are 'willing' to pay but don't because the Pareto Optimal (optimal point) intercepts with $200. The maximum amount of money they would pay is $260, therefore they have a 'gain' of $60.
- Producer surplus is related to marginal cost of producing one unit of any good. $150 is the cost of producing 1 MP3, that's where, for the producer, the supply curve begins. Because from there they can charge X more dollars and have profit. In Economic Theory, you can have a profit even when your marginal cost (cost) equals marginal benefit (price). Therefore, any additional dollar charged would mean a surplus for the producer.
But, what happens when government taxes a market (look now at the S+Tax curve)? First, supply contracts (moves to the left). The price definitely rises to the previous one+tax while the amount produced is reduced as well. Now, both the consumer surplus and producer surplus are negatively affected. New price is 210, while the amount produced is 4k MP3 players.
As you can see, that little triangle is what society loses overall. That is what tax does. Therefore, cutting taxes, among other things, will benefit society in general. Please keep in mind this an over-simplified economic model, and does not consider any other factors (
ceteris paribus). But that's necessary to understand what's going on. Hope this helps.