You should be just like me
Nick is described as being the only friend Tony has. The two spend a lot of time together even though they are not good for one another and as such, Nick is the only one who knows the struggles Tony goes through. Nick tries time and time again to push Tony to become just like him, claiming that only then Tony will find true happiness. The ironic idea is that even though Nick claims to have everything figured out and to be happy, he is far from it and is among the most unhappy people in the play.
On the assembly line
At the beginning of the play, Tony works on an assembly line together with countless other women and men just like him. During one instance, the people working on the assembly line talk about individuality and boast just how unique and free they all are. This scene is ironic because the workers are as far from being free and they are also far from being truly unique and individuals.
Money and happiness
The characters working a normal day job think that happiness can be found by having a lot of money. Because of this, all the characters make a lot of effort to gain as much money as possible and are willing to do everything to reach their goal. Ironically, the happiest people in the play are not those who have a lot of money, but rather those who almost have no money at all. This proves that happiness is not given by money but rather by their spiritual and mental state.
A friend worse than a foe
Tony is a truly depressing character. He is stuck in a job which brings him no satisfaction, has no family, no real purpose, and has only one friend, Nick. Tony lives for the frugal meetings he has with Nick at the local bar and looks forward to them. What is ironic is that even though Tony sees Nick as his only friend, he is far from being a true and helpful friend. In fact, Nick is in many cases worse than an enemy because he only brings Tony down. Because of this, the relationship between Tony and Nick is an ironic one.
We have no choice
The characters in the play feel stuck, almost as if they have no other choice but to live an unhappy life, stuck working in an unfulfilling job which leads them nowhere. The characters often describe themselves as if they are prisoners in a machine or simple cogs. Ironically, even though they feel like the world is keeping them, prisoners, this is far from being the truth. In fact, the reason why the characters can't move forward is that they limit themselves and do not let themselves move forward and advance.
