in⋅e⋅luc⋅ta⋅ble
   /ˌɪnɪ'lʌktəbəl/ Show Spelled Pronunciation [in-i-luhk-tuh-buhl] Show IPA
-adjective
incapable of being evaded; inescapable: an ineluctable destiny.

We think of ourselves as logical, as able to move in deductive order through a set of arguments from beginning to ineluctable conclusion.

The period from now until the end of the war in 1453 demonstrated an apparently ineluctable downhill slide.