The phrase "a universal theory" is correct and usable in written English.
It can be used when referring to a theory that is applicable in all cases or situations, often in scientific or philosophical contexts.
Example: "Einstein's theory of relativity is often considered a universal theory that applies to various aspects of physics."
Alternatives: "a comprehensive theory" or "a general theory".
It is a universal theory".
Remember too that he was not in search of a universal theory to explain biological diversification.
In Depth: Physics As physicists continue to search for a universal theory, new discoveries are aiding them in their quest.
The mere existence of two major approaches with different strengths calls into question whether either of them could serve as a basis for a universal theory of intelligence.
Here are a few questions D.A.R.P.A. posed to the "ists": Does the structure and function of stories vary considerably across cultural contexts or is there a universal theory of story?
Despite decades of effort, a general consensus on the validity of a universal theory for the large variety of glass systems is lacking2,3 partly because of difficulties encountered in the experimental testing of the theoretical predictions4,5.
He does not fall for the Hobbesian folly of inflating a still inchoate method into a decisive, universal theory of morality.
By the 1970s, however, flaws and gaps in these comprehensive theories led many psychologists to conclude that learning could not be represented by a single universal theory.
Finally, a simple universal theory is proposed for the first time to predict the pull-out force for an arbitrary sliding in a given MWCNT, directly from the diameter of the critical wall.
Einstein's classical theory of gravitation, as well as the equation of h ab, is not conformally invariant, thus could not be considered as a comprehensive universal theory of gravitational fields.
The output of a realist evaluation is a programme theory or a middle-range theory (not a universal overarching theory), which provides a plausible explanation for the outcomes of the intervention; it cannot make predictive statements about the intervention.
