The real things are real.
The ideas in your mind about the things are ideas in your mind.
The first rule of tautology club is the first rule of tautology club.
Ideas in your mind about the things include:
- What you experience through your senses (empirical apperception or qualia): how it sounds, how it looks, how it feels to the touch, how it tastes, how it smells
- How you categorize, name, and otherwise assemble your sensory experiences into knowledge: boundaries, kinds, classifications, purposes, applications, relationships to other things
- How that makes you feel emotionally (affect)
The facts about the thing are descriptions of what interactions with the part of reality so-described will make you sense, whether directly (the cat is the thing that makes you hear "meow"), with the mediation of an apparatus (the cat is the thing that will make you see a picture of numbers corresponding to the cat's weight if you put it on a scale), or with the mediation of another person (the cat is the thing that will make you hear the sound of your lab assistant saying "Ow, she bit me!" if you instruct your lab assistant to grab the cat by the tail).
You can abstract yourself and your apparatus out of these descriptions by mapping the sensed qualities to quantifiable measurements which could be mapped to any qualia of any creature and/or any display on any combination of well-calibrated apparatus given only the definitions of the units. For instance, instead of saying, "The cat is a process which has such quality that when we put it on the scale, I see the symbols for 5 kilograms," we can say "The cat is a process which has such a quality that, when its mass is measured by whatever means is used, will return a measurement equivalent to 5 kilograms in whatever units are used." We abbreviate this by saying "the cat's mass is 5 kilograms", but it can be important (especially in quantum mechanics) to remember that what we are ultimately describing is a thing that reality does and not our a way that reality is (except as: "reality is such that it does such and such thing").
Consider my assistant Glorp the Space Alien.
Glorp is an intelligent space alien who thinks in binary, doesn't distinguish intuitively between distances less than a kilometer or times less than an hour (it's a very big, cold space alien), and is capable only of sensing through its sense of wetness (which humans don't have) could still, if it was told what aspects of its environment it was supposed to define as a process and map to "a cat" and what a kilogram was, figure out not only that there was a cat, but that the cat corresponded to a measurement of 5 kilograms. It would think about cats as brief causes of micro-fluctuations in regional wetness profiles that one needs sophisticated apparatus to measure at all, whose mechanics are as unintuitive to them as quantum mechanics are to us. Its symbolic representational thoughts about the cats would be in a binary encoding whose very symbols, WET and NOT WET, are incomprehensible to us. But we could still teach it all there is to know about cats, except for how they make you feel or what it's like to sense them (or even to see, hear, smell, taste, or touch at all), just as they could teach us everything there is to know about regional wetness profiles, except for what it's like to sense one, or how it makes them feel. The regions, the water, and the cats, are real. The sensations and the feelings are internal and non-arbitrary; we can try to describe them to one another by analogy, but we'd only be guessing. The assembly into knowledge - which part of reality is the region, which part of reality is a cat - is arbitrary, and therefore transferrable if it can first be encoded in terms of measurements with objectively defined units.
