The argument is made that gays are deprived of the right to marry the person they love but there are many restrictions placed on marrying someone we may love. For example, a male cannot legally marry his biological mother, regardless of how much he loves her. In fact, the same male cannot legally marry his biological 25 year old daughter, regardless of the depths of their love. The law prevents everyone from entering into this type of union whether straight or gay. Denying gay marriage is not discrimination when no one is legally allowed to marry of the opposite sex.
I accept this challenge and will now offer my rebuttal and arguments.
To begin with, a rebuttal will be offered to my opponent's round 1 exposition.
The first part of my opponent's exposition is based on listing existing laws, rules, and facts. Those facts are indeed correct; in the status quo, same sex marirage is indeed not allowed, and gay people are indeed still allowed to marry people of the opposite sex. This, however, proves nothing. My opponent has merely listed a few existing laws and rules, but this is, unfortunately for him, not an argument.
These facts mean nothing as long as my opponent doesn't explain why those presently existing laws are good, or at least more beneficial than rules and regulations that would allow same sex marriage. He has failed to do so in his exposition.
He then goes on to state that gays aren't allowed to marry for the same reasons due to which a son cannot marry his mother, or a daughter her father. That is, however, utterly and completely false.
The marriages my opponent mentions are disallowed due to obvious biological and medical reasons. I shall simply refer to the example he offered - harboring romantic feelings as well as a desire to marry/sexually/physically possess one's mother or father is a known medical condition known as the Oedipus complex. 
Furthermore, it has been observed that offspring which result from coitus in such a relationship have a much greater risk of being afflicted by genetic disorders and mutations.
As opposed to what has been stated, there has, up to the present, been no evidence that if, perhaps, a gay couple was to a adopt a child, said child would be subject to certain medical disorders and diseases as a direct consequence of the foster parents being gay. Indeed, homosexuality itself isn't qualified as a disease or disorder, but as an orientation.
While there are those who still hold the view that homosexual activity is "unnatural" or "dysfunctional", research has shown that homosexuality is an example of a normal and natural variation in human sexuality and is not in and of itself a source of negative psychological effects. 
Given that qualification and the facts stated above, it is safe to conclude that the reasons my opponent stated in his exposition as to withholding the right to marriage from homosexual couples are completely irrelevant.
After offering my rebuttal, I shall now state my case as to allowing gay marriage.
LACK OF EVIDENCE OR RELEVANT REASONS AGAINST
Many people have a problem with gay marriage, or homosexuality per se, and it has indeed become a major issue in the modern world. However, the claims of those who make up the opposition towards gay marriage have no logical foundation. In general, the reasons they name are:
a) Gay marriage is incompatible with their religious views
b) They find gay marriage disgusting/revolting/unnatural/a product of a disease
c) They believe gay couples threaten marriage as an institution
I shall now dismantle the so-called logical foundation behind those reasons.
Let's begin with religion. Some people deem gay marriage unacceptable due to it being incompatible with their religious views and viewpoints - that is, their religion condemns gay marriage. Due to this being a very common argument against gay marriage, I shall be very clear:
Honestly, who cares about what your religion does or does not condemn? Religion is not a rule. It isn't a universal law that everyone must follow, just because you, an oh-so-important anonymous person, follow it. It does not give one a right to forbid others from certain actions and lifestyles. Religion is personal and it should stay that way - one's religion has no place in other people's affairs.
Allow me to illustrate - say your views forbid me the consumption of apples. According with your views, you will not eat apples. It isn't logical or rational, however, that you should move to make the consumption of apples universally illegal, simply because you do not eat them.
Now, as for people who find gay marriage disgusting (or any other synonym for the word "disgusting") - once again, who cares? Personally, I find such views to be remnants of ages past - illogical, irrational, and primitive. However, I will not attempt to withhold propagators of such views their rights, simply because I do not agree with their viewpoint. It is the same as it is with religion; one's personal views have no place in another's affairs and rights.
Each person has a right to personal freedom and security of person - since everyone has right to an opinion and viewpoint, no viewpoint must encroach on and hinder the beliefs of others.
This has been recognized by the international community as well :
ARTICLE 1 OF THE UNIVERSAL DECLARATION OF HUMAN RIGHTS:
All human beings are born free and equal in dignity and rights.They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.
ARTICLE 2 OF THE UNIVERSAL DECLARATION OF HUMAN RIGHTS:
Everyone is entitled to all the rights and freedoms set forth in this Declaration, without distinction of any kind, such as race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status. [...]
ARTICLE 3 OF THE UNIVERSAL DECLARATION OF HUMAN RIGHTS:
Everyone has the right to life, liberty and security of person.
ARTICLES 18 & 19 OF THE UNIVERSAL DECLARATION OF HUMAN RIGHTS:
Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief, and freedom, either alone or in community with others and in public or private, to manifest his religion or belief in teaching, practice, worship and observance.
Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference [...].
Each one of these declarations confirms what I've stated concerning personal views, as well as proving there is an uniform agreement in the international community concerning said views and rights.
As for the belief that homosexuality is a disease, and gay marriage, by extension, an "abomination"; that has been dealt with in my rebuttal.
Finally, I will address the belief that gay marriage threatens marriage as an institution.
"Honey, we have to get a divorce, I can stand this no longer! All those gays wanting to marry have ruined our marriage!" - said no one, ever. Gay marriage holds no relation no heterosexual marriage whatsoever. It cannot be more simple than that; there is no argument or reason that has ever been offered to substantiate the claim of the instituion that is marriage being threatened.
After this rebuttal, it is obvious that there are no relevant reasons to forbid gay couples to marry, so why should they not? Allowing gay marriage would prove that modern society has advanced to a new level of conscience, that it works towards preserving human rights. Indeed, who has the right to deny homosexual couples the opportunity to marry?
Love brings homosexual people together just as much as heterosexual people, whereas it is plain, illogical hate that drives the opponents of gay marriage.
The Merriam-Webster dictionary offers this as a plausible definition of marriage: the state of being united to a person of the same sex in a relationship like that of a traditional marriage 
Marriage has no universal definition - the only constant is love that brings couples together.
No one has a right or logical foundation to deny that.
Back to my opponent.
notght forfeited this round.
I extend all of my arguments due to my opponent forfeiting.
notght forfeited this round.
I, once again, extend all of my arguments due to my opponent forfeiting, and thus end the debate.
It is unfortunate there was no debating in this debate.