How should taxes be made equitable?

[QuestioningStudent]

This may perhaps seem an odd question, but in several debates and discussions I've had of late, this issue has come up. It seems that there are about four real ideas for taxing people in a fair and equitable fashion, and I'd appreciate some input. I am not aware of any technical terms for these concepts, so bear with me, please.

Ideas for equitable tax burden distributions:
1)Tax people in proportion to the value they derive from society; this argument has generally been presented as equating to taxing the goods that a taxpayer consumes, e.g. a national sales tax.
Does not require an income tax, and is, in fact, antithetical to it, as it supposes that you only benefit from the money you spend, which will not by necessity be all that you earn.

2)Taxing everybody for the same absolute amount, i.e. the exact same amount of money. Everybody pays the same in this system, every shares the financial burden for the society "equally."
Does not require an income tax, and is diametrically opposed to it.

3)Taxing everybody for the same percentage of their wages. This says everybody owes the same portion of their work in exchange for the benefits of the society, not the same dollar amount, as the prior system means everyone contributes the same portion of their time and money to the system, and the latter does not.
Obviously requires an income tax.

4)Distributing the burden of taxation equally; that is, recognize that (hypothetical numbers here) a 5% tax on a person making subsistence level wages might be equivalent in terms of affecting the taxpayer's ability to purchase goods and survive as a 45% tax on a person at a much higher income level. In this concept, equal discomfort due to taxation is the ideal, not equal dollar values or equal time, etc.
Obviously requires an income tax.


So what do you all think? What's the best system? Why? How do you convince someone (particularly someone that favors the first system) that they're wrong?

Thanks.