If there is a contradiction between two statements made by the same witness at different times, can that contradiction affect the credibility of the witness?

If there is a contradiction between two statements made by the same witness at different times, that conflict could adversely affect the witness' credibility, whether or not the pre-trial statement was made under oath. But that would not create the conflict referred to in Jutt v. Doehring, which in my view requires that there be conflict between two opposing witnesses, as to the existence of a fact essential to the claim or the defence. Where there is self-contradiction by one witness, the inconsistency may diminish the credibility of that witness. Where the witness is a plaintiff who seeks summary judgment, a self-contradiction would be relevant to the issue of the merits of the claim. But it could not constitute procedural grounds to dismiss a plaintiff’s application for summary trial under R.18A(11)(a)(i).