For materialist dialectics, only that is positive (scientific) knowledge, which is gained through man’s social/historical experience and practice of life and through interaction (intercourse) with external reality (Nature) through his (man’s) labour and technology; to subjectively CHANGE Nature, of which he (man) is a (subjective) part. Brain-cooked subjective idealism of "logical categories" (even mathematics driven ones), fantasy, illusion, delusion, faith etc., can never give scientific knowledge.

A more fundamental criteria of positive knowledge is that with enhanced historical development it leads to the progressive realization of the "Freedom of the Will" of subjective man.

In philosophy, Emmanuel Kant “found it necessary to deny knowledge, to make room for faith”; while objective reality for Kant remains an “unknowable thing-in-itself”!! In physics, (specially after the appearance of the “Evil Quanta”); Albert Einstein “found it necessary to deny knowledge, by turning what is REAL to UNREAL and vice versa; to make room for faith. For Einstein, “Reality is merely an illusion, albeit a very persistent one.”: https://www.brainyquote.com/quotes/albert_einstein_100298

Even for classical physics (and materialist dialectics) there can be no Matter without Motion and no Motion without Matter. In relativistic physics, Einstein created (in thought) Motionless Matter m0 and Matterless Motion as p (relativistic momentum). Also in classical physics, Motion(Velocity) was measured with the help of a well preserved (at fixed temperature), inactive and standard Matter rod with a fixed length. In relativistic physics, Einstein and official physics. made (in practice) the Motion (velocity c) of Massless Matter (light) as the standard to measure the length of a Massive Matter Rod. So, relativistic physics is indeed “merely an illusion, albeit a very persistent one.”, for our modern "cosmologists" and “physicists” of faith! Amen!!