Are there other solutions to 1+1=2?

[asdfghjklqqww]

one plus one equals three if


one equals 1.5

 

[Char. Limit]

one plus one equals three if


one equals 1.5

...yes, iff $1=1.5$, then $1+1=3$. However, $1\neq1.5$, so therefore $1+1\neq3$.

 

[Hurkyl]

...yes, iff $1=1.5$, then $1+1=3$. However, $1\neq1.5$, so therefore $1+1\neq3$.

While true, this is an invalid argument. Fallacy of the inverse or something like that.