Berkeley on Substance Ideas in Mind of God Ideas in Mind1 Ideas are simply what they are they do not inhere in anything else—that is there is No material substrate To be is to be perceived=esse es percipi
Locke on knowing the world SELF WORLD Substance=“A something I know not what.’ Act of Reflection Primary Qualities In Mind Primary Qualities in Things Secondary Qualities Substance is in principle unknowable
Aristotle on Knowing the World Matter=substrate/potential Form=matter in act Potential=matter/substrate Potential=Mental Substrate Abstracted Forms being Thought in Mind SUBJECT=SOUL/MIND OBJECT Actual Field of Perceptual Interaction Material substrate=upokeimenon The Mind is in a Sense All Things The Mind(Soul) will, through time, exhaust all potential forms and powers of an object—it will fully know it. There is nothing that is, in principle, unknowable
Descartes on Knowing the World Mental Substance Thinking Thing Non-spatial Material Substances Extended things Pineal Gland What are we thinking about an object may in no way correspond to any actual Characteristic in the thing it-self (cf. evil genius). There is no direct connection between mind and world.