Text: But if inequality becomes so great that people lose all hope of changing their relative positions, then the incentive to oversave disappears, and the inequality could begin to shrink.
Entailment: However, if inequality becomes so great, that people lose all hope of changing their relative positions, then the incentive to oversave disappears, and the inequality could begin to shrink.
Contradiction: But if inequality starts shrinking so much that people don't care about their relative positions anymore, then the incentive to spend disappears, and the inequality could begin to grow.