The phrase "purpose in itself" is correct and usable in written English.
You can use this phrase when you're talking about a goal or activity that is valuable or important for its own sake, and not as a means to other goals or activities. For example: "Travelling is a purpose in itself; it helps us build knowledge and understanding of different cultures around the world."
Papandreou said his call this week for a referendum, which sparked panic on global financial markets and infuriated European partners, "was never a purpose in itself", and he would be happy if the vote were not held.
Her letter-writing acquires a purpose in itself.
This is because the cleaning practice is not a tool but a purpose in itself.
I also said, that I think that finance is not a purpose in itself, it's a tool.
Of course, mineral soil C sequestration is not a purpose in itself, but a co-benefit of practices applied to improve soil health and, hence, productivity34.
The final result is not an purpose in itself, but a means for providing the student with a deeper understanding of spatial design that he will be able to apply later on into practice.
A conspiracy is sufficiently described as a combination of two or more persons, by concerted action, to accomplish a criminal or unlawful purpose, or some purpose not in itself criminal or unlawful, by criminal or unlawful means, and the rule is accepted, as laid down by Chief Justice Shaw in Com.
Only those combinations intended "to accomplish some criminal or unlawful purpose, or to accomplish some purpose, not in itself criminal or unlawful, by criminal or unlawful means" could be prosecuted.
An endurance test without end, she might have said, for a purpose only in itself.
That process — the conversation among curators, the parsing of symbolism and engagement with the museum's purpose — would in itself deflate some of the object's symbolic power.
Justice is something whose purpose lies in itself.
