An Approach to General Systems Theory

Pages 36 and 37.

"When investigating nature, we confine our examination to some part that interests us at a given time. This segment of nature we call object, the entire remaining part of nature being termed environment. (...) Let us note that the boundaries between an object and its environment cannot be stated quite perfectly. There is always some uncertainty in any classification of the nature to an object and its environment. Our facilities do not permit us to study objects in all their complexity. On the chosen object, we therefore observe or measure appearances of certain attributes or, in other words, we observe or measure values (not necessarily magnitudes) of certain quantities. The choice depends on what we consider to be of interest on the given object, or what we regard as important to the given purpose.&quot

L'Homme Machine

Page 14 of the Open Court Classics edition.

"IL ne suffit pas à un sage d'étudier la nature et la vérité; il doit oser la dire en faveur du petit nombre de ceux qui veulent et peuvent penser; car pour les autres, qui sont volontairement esclaves des préjugés, il ne leur est pas plus possible d'atteindre la vérité, qu'aux grenouilles de voler."

David Hume

An Enquiry Concerning Human Understanding

Sect. VII. Of the Idea of necessary Connexion, Part I.

"THE great advantage of the mathematical sciences above the moral consists in this, that the ideas of the former, being sensible, are always clear and determinate, the smallest distinction between them is immediately perceptible, and the same terms are still expressive of the same ideas, without ambiguity or variation."

From a logical point of view

"To be is to be the value of a quantified variable."