He pointed to the contemporary growth of civil liberty and religious liberty, and these are conditions of moral improvement.

So far his argument coincides in principle with that of French theorists of Progress.

But Kant goes on to apply to these data the debatable conception of final causes, and to infer a purpose in the development of humanity.

Only this inference is put forward as a hypothesis, not as a dogma.
It is probable that what hindered Kant from broaching his theory of Progress with as much confidence as Condorcet was his perception that nothing could be decisively affirmed about the course of civilisation until the laws of its movement had been discovered.

He saw that this was a matter for scientific investigation.