>Nope because I won't consider the door already opened. After door one, there are only 999 to choose from. The odds change.
>

The point is that after you picked a door he opens 998 doors where there is no car ( - he knows where the car is). That makes the odds of the last door 999/1000

Think about it

>>No, you make the same mistake as I originally did
>>
>>To make it clearer, say you have 1000 doors
>>
>>You pick one. The odds that you have the door with the car = 1/1000
>>
>>Then, he opens 998 other doors (with goats behind them)
>>
>>The odds that the car is behind the door you did not pick = 1000/1000 - 1/1000 or 999/1000
>>
>>
>>
>>So, you better switch - I would if I were you