Dick DeShaw 370 Barrie St Kingston On K7K 3T3
Dear Dr Fuchs:
Has anyone commented to you on the similarity of QBism and Spinoza’s ‘Being of Reason’? As Spinoza says: “Some things are in our intellect and not in Nature; so these are only our own work and they help us to understand things distinctly. Among these we include all relations which have reference to different things. These we call, ‘beings of reason.’ (God, Man and His Well Being, in Edwin Curley’s The Collected Works of Spinoza, Vol. 1, p. 92)
Spinoza believed only things and their actions exist and our thinking about them is only a being of reason or imagination. Spinoza’s three kinds of knowledge can be related to Bayesian probability:
1) Opinion (Vague experience, signs, imagination) = subjective Bayesian
2) Reason (Possessing common notions and adequate ideas) = objective Bayesian
3) Understanding (Intuitive science – from adequate ideas to essence of things) = actuality (a singular thing demonstrates itself to consciousness).
Ethics Part II, Prop 40, sch 2. p. 141 in Curley, op.cit. (paraphrased)
Of course, Spinoza believed ‘probability’ was only a being of reason and didn’t exist in nature.
He has been damaged by traditional philosophic interpretation both by labelling him a ‘rationalist,’ and by dismissing his early works; ‘The Emendation of the Intellect as well as God, Man and His Well Being, where he laid the foundations of his theory of knowledge (which is generally labeled as unimportant and immature).
Spinoza’s later works such as the Ethics, were an expression of what he believed, not his foundation. I have explored these issues in a paper on my blog; ‘Spinoza; The Man Who Changed the God Game.’ My blog is: Spinoza On Science & Stress.
A friend who is into metaphysics challenged me to put what I believe into syllogistic form. Here’s what I sent him:
WHAT I BELIEVE
‘Equal’ and ‘whole is greater than the part’ are the axioms of human thought. (Euclid)
The True and Real is the power set that contains these axioms. We call this set ‘logic/mathematics.
Therefore, logic/mathematics is the foundation of human thinking.
Therefore I am innately logical/mathematical.
Logic/mathematics is a language of abstract symbols
Ordinary language uses metaphor (like) and not abstract symbols
Therefore ordinary language is not always logical (or mathematical)
I have to use ordinary language to express my thoughts.
Therefore my thoughts may not always be logical.
I sent him this, ‘What I Believe,’ along with a copy of ‘QBism, the Perimeter of Quantum Bayesianism’ which I found immediately after reading Hans Christian Von Baeyer’s piece about you in my June issue of Scientific American. I had just finished the first of many readings of your work.
Sincerely, Dick DeShaw