LOGIC :; The principle governing human intellection. Its nature may be **deduced** from examining the following propositions, both of which are held by human beings to be true and often by the same people: “I can’t so you musn’t,” and “I can but you musn’t.”

— the happening world (15) “Equal and Opposite”

To make our position clearer, we may formulate it in another way. Let us call a proposition which records an actual or possible observation an experiential proposition. Then we may say that it is the mark of a genuine factual proposition, not that it should be equivalent to an experiential proposition, or any finite number of experiential propositions, but simply that some experiential propositions can be **deduced** from it in conjunction with certain other premises without being deducible from those other premises alone.

— p. 20 (Language, Truth, and Logic (1936))

It is possible to express the laws of thermodynamics in the form of independent principles, **deduced** by induction from the facts of observation and experiment, without reference to any hypothesis as to the occult molecular operations with which the sensible phenomena may be conceived to be connected; and that course will be followed in the body of the present treatise. But, in giving a brief historical sketch of the progress of thermodynamics, the progress of the hypothesis of thermic molecular motions cannot be wholly separated from that of the purely inductive theory.

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Ruskin's much-derided moral theory of art was part of an attempt to show that this human activity, which we value so highly, engaged the whole of human personality. His insistence on the sanctity of nature was part of an attempt to develop Goethe's intuition that form cannot be put together in the mind by an additive process, but is to be **deduced** from the laws of growth in living organisms, and their resistance to the elements.

— Section 3: A Note on Ruskin's Writings on Art and Architecture

We shall see that the mathematical treatment of the subject [of electricity] has been greatly developed by writers who express themselves in terms of the 'Two Fluids' theory. Their results, however, have been **deduced** entirely from data which can be proved by experiment, and which must therefore be true, whether we adopt the theory of two fluids or not. The experimental verification of the mathematical results therefore is no evidence for or against the peculiar doctrines of this theory.

— A Treatise on Electricity and Magnetism (1873), §36.

I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses; for whatever is not **deduced** from the phenomena is to be called a hypothesis, and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy.

— Letter to Robert Hooke (15 February 1676) [5 February 1676 (O.S.)]

We shall see that the mathematical treatment of the subject [of electricity] has been greatly developed by writers who express themselves in terms of the 'Two Fluids' theory. Their results, however, have been **deduced** entirely from data which can be proved by experiment, and which must therefore be true, whether we adopt the theory of two fluids or not. The experimental verification of the mathematical results therefore is no evidence for or against the peculiar doctrines of this theory.

— James Clerk Maxwell (1873)

I have not as yet been able to discover the reason for these properties of gravity from phenomena, and I do not feign hypotheses. For whatever is not **deduced** from the phenomena must be called a hypothesis; and hypotheses, whether metaphysical or physical, or based on occult qualities, or mechanical, have no place in experimental philosophy. In this philosophy particular propositions are inferred from the phenomena, and afterwards rendered general by induction.

— As translated by I. Bernard Cohen and Anne Whitman (1999).