When a Hadith fulfils the conditions of tawātur, it gives certain knowledge, not merely the thought that it might be true.
This is called ʿilm qaṭʿī badīhī (علمِ قطعی بدیہی): certainty arising from the report reaching us in this way.1
1. Qaṭʿī (قطعی): certain. Badīhī (بدیہی): knowledge arising from this manner of transmission, without needing to construct a separate argument to reach it.