I see... excellent points.
Let me therefore amend my prior statement:
1. No matter what you think you know, you still need food, water, shelter, sleep, a place to relieve yourself that won't contaminate any of the prior four, safety,
and a satisfactory quality of life. If your philosophy doesn't help you acquire these things, that philosophy is meaningless.
There is no 2-5.
There - survival plus satisfaction.
In spite of the side-track, though, I think what I was getting at was that some philosophy - for example, ideas of solipsism or acosmism - is ultimately pointless, when we consider that these ideas give no advantage in the survival equation - nor, indeed, in the quality of life equation. As pointed out several times to Darren, unless the acosmist can supercede the apparent physical world, 'knowing' that the physical world is 'unreal' is pointless and meaningless.
Anyway, language being one of my many weak points, I thank you both (Battijer and Robobobobomamarama) for clarifying and challenging the position I believed that I held.
(I have to keep using the dragon icon or Darat will think I don't appreciate it. Or was it someone else who added that? Uh-oh, memory failing...)