List<List<ProofStepBwChGoal>> currentLevelProofSteps,
Clause toProve, Literal currentGoal,
Map<Variable, Term> bindings) {
if (currentLevelProofSteps.size() > 0) {
ProofStepBwChGoal predecessor = new ProofStepBwChGoal(toProve,
currentGoal, bindings);
for (List<ProofStepBwChGoal> steps : currentLevelProofSteps) {
if (steps.size() > 0) {
steps.get(0).setPredecessor(predecessor);
}