# In which scenario is this possible?

1. Jul 4, 2007

### Werg22

Here is a little brain teaser:

You are my brother, and your mother is my mother. However, your father is my son's brother. If no incest occurred, how is that situation possible?

2. Jul 5, 2007

### davee123

First off, by "brother" you have to mean "half-brother" in at least one, if not both uses of the word. So, because it must mean "half-brother" in at least one, since your wording affords no difference between the two, then BOTH may be half brothers, making the problem trivial.

Imagine:

"MY MOTHER" and "MY FATHER" have a child, which is "ME".

"ME" and Pat have a child, "MY SON".

Pat and Terry have a child, "YOUR FATHER"

"YOUR FATHER" and "MY MOTHER" have a child, "YOU".

DaveE

3. Jul 5, 2007

### Werg22

You are correct. It has to be assumed that they are half-brothers though since if they were real brothers it would make the scenario impossible.

4. Jul 5, 2007

### DaveC426913

I was wondering along those lines too, but it stretches my idea of a "valid" teaser, because the trick to it is so obvious while at the same time rendering the problem trivial.

5. Jul 5, 2007

### Schrodinger's Dog

All questions are trivial when you know an absolute answer.

What interests me is seeing a grey one though, food for thought, like "Einstein's" riddle.