From the Jain perspective, the point is not that sequence alone proves a substance in a crude way, but that changing states require a real enduring basis.

In Jainism:

• Jīva is a real, conscious substance.
• Its modes change: knowledge, memory, delusion, purity, bondage, and liberation all occur as states of the same jīva.
• Karma is not just a causal pattern; it is a real subtle material bondage that attaches to jīva.
• Memory is explained by continuity of the same conscious substance through changing conditions.
• Liberation is not merely the ending of a process; it is the actual release of karmic bondage from the jīva, which then exists in its pure state.

So the Jain reply is:

• Conditions explain change in states.
• But conditions do not explain the unity of the changing experiencer.
• If there is only a stream of conditions, Jainism says there is no true owner of bondage, no true experiencer of karmic fruits, and no true liberated being.

Jainism therefore holds that:

1. Continuity without a persistent jīva is insufficient to account for responsibility, karmic bondage, and liberation.
2. Memory is not merely sequence; it is a function of the same conscious substance retaining identity through change.
3. Liberation requires a real soul to become free of karmas; otherwise “freedom” becomes only a description of a causal process, not the emancipation of a conscious self.

So the Jain position is not that substance is an unnecessary addition, but that without jīva, the doctrines of bondage, merit, demerit, remembrance, and mokṣa lose their proper ground.

In short:

• Buddhism emphasizes causal continuity.
• Jainism affirms causal continuity within an enduring conscious jīva.

That is the core difference.