In order to secure the #2 seed, the magic number is 3.
The Knicks can do this winning against Cleveland, Charlotte, and Atlanta (even losing to Chicago and Indiana). You can argue that they want to wrap up as soon as possible in order to rest other players.
However, not having anyone else get hurt is a higher priority, even to the point of ending up in the #3 seed.
Even if they cannot win all three games against the weaker opponents, if Indiana loses to Brooklyn and/or the Knicks, then the magic number becomes 2, 1, or 0.
There is even an argument that the Knicks WANT to lose to Chicago tonight. It goes like this: If Chicago can retain the #5 seed and win the first round, then they can beat up on Miami physically in the second round, helping the Knicks. If they drop to the #6 seed or lower, then they could do the same to Indiana (OK but not really necessary for us), or potentially the Knicks (a nightmare scenario for us). Therefore, losing tonight might actually be a good thing for us (playoff-wise).
I understand that psychologically getting swept in the regular season by the Bulls is hard to swallow, but getting to the NBA Finals might be the end result of losing to Chicago tonight (if say, Wade or Bosh gets hurt in a series against the Bulls).