how can i explain that a virus can be removed with software?

i was talking to a couple of my friends both computer repairmen and we were talking about viruses and i said that i read that a computer virus can be removed with software and they laughed at me. they explained that this myth was started right alongwith the great pumpkin or the belief in the easter bunny. the only way to remove a virus and be asured that the virus is gone is to format the hard drive that is to delete the infected petition and replace it with a fresh petion and new drivers.

I said then there is none at all and they told me that a computer repairman came up with that saying to drum up business that virus will eat their hard drive then to their ram and then when it gets into the registry a new tower has to be bought to replace the old one and then they said that every year you have your computer is like fifty years in human years so i laughed at them and said my computer is two years old and so it is two hundred years old they replied now you got it.

so if someone tells you to correct your virus with software just laugh at him and do the smart thing and take it to a computer repairman that is unless you can do it yourself. so now i ask you have i destroyed the myth? if you must disagree please be civil with your answers but if two rrepairman tells you go to a repairman and ask him and he will agree with me so go ahead and tell me what software can remove viruses l o l