6. Do the Celtics believe they can win?

The Toronto Raptors didn’t get swept in the second round solely because they had no self-belief, but they were blown out four straight times because they had no self-belief.

Boston won 53 games during the regular season — good enough for the No. 1 seed. The Celtics have now made the Conference Finals and have a 25-percent shot of landing the first overall pick in Tuesday’s Draft Lottery. It would be very easy for them to pack it in and say this was a successful season, especially after they made no attempt to improve at the trade deadline, ceding the East to Cleveland in the minds of some.

They won’t lay down — at least not as easily as Toronto did. But if Cleveland is up by double digits heading into the fourth quarter of Game 1, it will be very easy for the Celtics to quit on themselves. If this happens a couple games in a row, it might be over before the halfway point in the series.

It’s cliche as hell, but the first step to pulling off an upset of this magnitude is thinking it’s possible.

If the Celtics can at least do that, they’ve got a chance.