The bifurcation fallacy is the fallacy of the ‘excluded middle’. Only two options are presented as possible, while there may be three, or even more.
In Latin, this is referred to as Tertium non datur ; ‘there is no third’.
Example 1
Either you cook now, or we’ll starve to death Harry!
But we had lunch two hours ago!
Obviously the first person is hungry, but the fact that they had lunch indicates there’s at least two other options
- He doesn’t cook, and they’ll not starve to death; just be a little hungry.
- She cooks, and they’ll not starve to death either.
Example 2
‘If you don’t love me, you must hate me.‘
‘But we’ve only just met!‘
When somebody uses a bifurcation fallacy at your first date, it may be best to pack your things! Obviously, person two is interested in person one, otherwise he would not have agreed to meet, but love is an emotion that can come over time, too, while the lack of love does not necessarily indicate hate.
Example 3
If you do not clean your room now, you will trip over all the mess you’ve made.
There are several alternatives here, for example:
- He does not clean the room, and is careful not to trip.
- He avoids his room, until he cleans it later.
- Somebody else cleans the room