I think the issue is with binding:
constructor(props){
super(props);
this.goBack = this.goBack.bind(this); // i think you are missing this
}
goBack(){
this.props.history.goBack();
}
.....
<button onClick={this.goBack}>Go Back</button>
As I have assumed before you posted the code:
constructor(props) {
super(props);
this.handleNext = this.handleNext.bind(this);
this.handleBack = this.handleBack.bind(this); // you are missing this line
}