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don't believe anything you can't see, touch, hear or smell, don't believe in ghosts, gods, spirits or phantoms because they're not real but figments of our imagination,

The individual can be touched, smelled, and heard.

The collective - or society - cannot be touched smelled or heard - only the individuals within a group.
Wise fella, your Dad.

Collectives are a concept.
Figments of imagination.

Leftist ideology (the collective) cannot exist without concept (phantoms) appearing as real.

...Are we finding a common ground?