How did Rene Descartes affect individualism and the privatisation of religion?

He had a very strong effect upon both individualism and what you describe as the "privatisation of religion" because of his meditation on primary philosophy. Some philosophers describe his Meditation as a a turn toward "subjectivism", rather than the individualism you describe. But Descartes was certainly clear on what he thought (no matter whether it is described as subjectivism or individualism) when he clearly wrote, quote:

DESCARTES:

But in conclusion, I find that I have insensibly reverted to the point I desired; for since it is now manifest to me that bodies themselves are not properly perceived by the senses, nor by the faculty of imagination, but by the intellect alone; and since they are not perceived because they are seen and touched, but only because they are understood [or rightly comprehended by thought], I readily DISCOVER that there is NOTHING MORE EASILY OR CLEARLY APPREHENDED THAN MY OWN MIND.

But because it is difficult to rid one's self so promptly of an opinion to which one has been long accustomed, it will be desireable to tarry for some time at this stage, that by long and continued meditation, I may more deeply impress upon my memory this NEW KNOWLEDGE.

[Of the Nature of the Human Mind; end of Meditation II].

That is a sharp turn toward what has been described as either subjectivism or individualism. And it wasn't really a "New Knowledge" given ancient subjectivists, who sometimes went as far as being solipsists --- sure of their own minds, but unsure of anything else.

As to religion's "privatisation":

...and when I consider that I doubt, in other words, that I am an incomplete and dependent being, the idea of a complete and independent being, that is to say of God, occurs to my mind with so much clearness and distinctness, --- and from the fact alone that this idea is FOUND IN ME, or that I who possess it exist, the conclusion that God exists, and that MY OWN EXISTENCE, each moment of its continuance, is absolutely dependent upon him, are so manifest, --- as to lead me to believe it impossible that the HUMAN MIND can know anything with more CLEARNESS AND CERTITUDE.

**** 1st paragraph of Meditation IV******

Descartes supplies us, in the paragraph quoted above, of a pretty strong personal argument for what you describe as the "privatisation of religion", given that the "ideas" of (1) God and (2) one's own personal existence seem to be, for Descartes, the most clear, distinct and, "hence", certain ideas that any individual can have in their own personal and private minds. So, perhaps, that may be what "privatisation of religion" means to Descartes afficianadoes.

Kevin.

Rene Descartes Religion

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