Speakpigeon
Contributor
- Joined
- Feb 4, 2009
- Messages
- 6,317
- Location
- Paris, France, EU
- Basic Beliefs
- Rationality (i.e. facts + logic), Scepticism (not just about God but also everything beyond my subjective experience)
I'm starting something without much of an idea as to where it might go. So, we'll have to see.
The target is a very precise mathematical point I'd like to clarify but I need to understand first exactly what concept mathematicians have of numbers. I plan to go into the question of the opposition between rational and irrational numbers, and then transcendental numbers, and then computable and non-computable numbers. And I'm no specialist! Sooo, if you fear it's just going to be too metaphysical, or perhaps too physical, feel free to move it accordingly.Just remember that there may not be anybody that will have anything to say on the subject over there.
So, I tend to make the distinction between three things. First, quantities. Physical quantities essentially but I'm not opposed to the idea of counting angels. Quantities, we suppose metaphysically, are things, perhaps properties, that exist somehow out there, in the physical world, like perhaps the always changing number of children in the courtyard or the varying quantity of potential energy of two bodies orbiting each other.
Second, there is our intuitive notion of quantities. I look at physical things and inevitably see them as quantities of other things. I see water as a quantity of molecules, humanity as a quantity of human beings etc.
Third, we have numbers. Numbers, I suspect, are thought of by most mathematicians essentially as symbolic expressions humans use to represent physical quantities. Mathematicians don't care much, I think, what they are used for. They are interested in their formal properties. Then, perhaps, physicists take a look at those numbers and try to figure out whether they might represent real physical quantities or what.
I'm going to stop here to see first if there is any interest in the subject. The question for now really is just this: What exactly is a number?
EB
The target is a very precise mathematical point I'd like to clarify but I need to understand first exactly what concept mathematicians have of numbers. I plan to go into the question of the opposition between rational and irrational numbers, and then transcendental numbers, and then computable and non-computable numbers. And I'm no specialist! Sooo, if you fear it's just going to be too metaphysical, or perhaps too physical, feel free to move it accordingly.Just remember that there may not be anybody that will have anything to say on the subject over there.
So, I tend to make the distinction between three things. First, quantities. Physical quantities essentially but I'm not opposed to the idea of counting angels. Quantities, we suppose metaphysically, are things, perhaps properties, that exist somehow out there, in the physical world, like perhaps the always changing number of children in the courtyard or the varying quantity of potential energy of two bodies orbiting each other.
Second, there is our intuitive notion of quantities. I look at physical things and inevitably see them as quantities of other things. I see water as a quantity of molecules, humanity as a quantity of human beings etc.
Third, we have numbers. Numbers, I suspect, are thought of by most mathematicians essentially as symbolic expressions humans use to represent physical quantities. Mathematicians don't care much, I think, what they are used for. They are interested in their formal properties. Then, perhaps, physicists take a look at those numbers and try to figure out whether they might represent real physical quantities or what.
I'm going to stop here to see first if there is any interest in the subject. The question for now really is just this: What exactly is a number?
EB
