Charles S. Peirce
[Lecture on Practical Logic]
MS 191 (Robin 393); Writings 3, pp. 8f :
I suppose that the fundamental proposition from which all metaphysics takes its rise is that opinions tend to an ultimate settlement & that a predestinate one. Upon most subjects at least sufficient experience, discussion, and reasoning will bring men to an agreement; and another set of men by an independent investigation with sufficient experience, discussion, and reasoning will be brought to the same agreement as the first set.
Hence we infer that there is something which determines opinions and which does not depend upon them. To this we give the name of the real. Now this real may be regarded from two opposite points of view.
In the first place, to say that thought tends to come to a determinate conclusion, is to say that it tends to an end or is influenced by a final cause. This final cause, the ultimate opinion, is independent of how you, I, or any number of men think. Let whole generations think as perversely as they will; they can only put off the ultimate opinion but cannot change its character. So the ultimate conclusion is that which determines opinions and does not depend upon them and so is the real object of cognition. This is idealism since it supposes the real to be of the nature of thought.
But, in the second place, a cause precedes its effect. And moreover the ultimate conclusion though independent of this or that mind is not independent of mind in general. The real, therefore, which determines thought but does not depend upon it, is not the last conclusion but the first premiss or what produces the first premiss,a something out of the mind and incommensurable with thought.
Since experience proceeds from the less general to the more general, the last conclusion is general, and so the first view is realistic, while the second from a like reason is individualistic. In the first view, the real is in one sense never realized since though opinion may in fact have reached a settlment in reference to any question, there always remains a possibility that more experience, discussion, and reasoning would change any given opinion. In the second view also the real is a species of fiction for that which is logically singular,or is determined with reference to every quality,can from the continual change which is constantly taking place not remain
for any time however short, (Daniel Webster, for example, is a class embracing
Daniel Webster under 50 years of age & Daniel Webster over 50 years of age) and
consequently does not exist as absolutely determinate at all.
Upon either view therefore the real is something ideal and never actually exists. But it is true on the one hand that thought tends to a determinate conclusion and on the other that if anything is true, true determinations without number are true
of it. We ought therefore to discard the conception of the real as something actual
and to say simply that only thought actually exists and it has a law which no more
determines it than it by the mode in which it acts makes the law. Only this law
is such that in a sufficient time it will determine thought to any extent.