The phrase "a natural thought" is correct and usable in written English.
It can be used when referring to an idea or notion that seems instinctive or intuitive.
Example: "After considering the situation, it was a natural thought to reach out for help."
Alternatives: "an instinctive idea" or "a common notion."
A natural thought here is that semantic rules effect a distinction between (semantically) correct and incorrect use of an expression.
It is a natural thought that no matter under what channel assumption, secrecy capacity achieved by security-oriented designs would be higher than that achieved by traditional designs.
A natural thought, then, is that the content of a name its sense is some condition which the referent of the name uniquely satisfies.
"It certainly is not a natural thought to run gasoline in a diesel engine, but when you control it properly, then not only can it be done, but you can achieve very impressive efficiency numbers, across the board.
A natural thought to have about sentences with referring nominal concrete mass expressions (e.g., "Alvin drank the water that Roderick poured" or "The coffee in that cup is too hot") is that the expressions refer to portions of matter, which are themselves made up of smaller bits of matter.
The excuse "I couldn't help it" or "I was forced to do it" is often enough to render blame inappropriate, so it's a natural thought that someone can only be blamed for those things that he could have helped, or wasn't forced into in other words, for those things that he chose of his own free will.
The Classical Incompatibilist Argument is merely a codification of this natural thought.
The natural thought is that a type is the set of its tokens, which is how Quine sometimes (1987, p. 218) construes a type.
The natural thought is that an expression should count as permutation-invariant just in case its extension on each domain of objects is invariant under all permutations of that domain.
Trauma was a strange thing, because you could be unaware of its presence, like diseased cells lurking in your body (a natural enough thought in a hospital) or like bulbs that would break the soil's surface only when stirred in their depths by the penetrating warmth of the sun.
A natural first thought is that they are explicit agreements, such as promises or contracts, enacted either by parties to the convention or by people suitably related to those parties (such as their ancestors).
