Cartwright is a member of the "Stanford School" of the philosophy of science, including John Dupré, Peter Galison, Ian Hacking, and Patrick Suppes. They are polemicists against the "unity of science," a notion that goes back to the Vienna Circle. Following Dupré, they defend the "Disunity of Science." Members of the Vienna Circle powerfully attacked metaphysics. Dupré's book The Disorder of Things is subtitled "Metaphysical Foundations of the Disunity of Science."

Cartwright is perhaps best known for her provocative book How the Laws of Physics Lie."

She writes...

Philosophers distinguish phenomenological from theoretical laws. Phenomenological laws are about appearances; theoretical ones are about the reality behind the appearances. The distinction is rooted in epistemology. Phenomenological laws are about things we can at least in principle observe directly, whereas theoretical laws can be known only by inference. Normally for philosophers ‘phenomenologlcal and ‘theoretical’ mark the distinction between the observable and the unobservable.

Physicists also use the terms 'theoretical’ and ‘phenomenological’. But their usage makes a different distinction. Physicists contrast ‘phenomenological’ with ‘fundamental’.

(How the Laws of Physics Lie, p.1)

Cartwright says phenomenological laws describe what happens. The terms 'theoretical’ and ‘phenomenological’ separate laws which are fundamental and explanatory from those that merely describe.

She writes...

The divide between theoretical and phenomenological ^ commonly separates realists from anti-realists. I argue in these essays for a kind of anti-realism, and typically it is an antirealism that accepts the phenomenological and rejects the theoretical. But it is not theory versus observation that I reject. Rather it is the theoretical as opposed to the phenomenological.

In modern physics, and I think in other exact sciences as well, phenomenological laws are meant to describe, and they often succeed reasonably well. But fundamental equations are meant to explain, and paradoxically enough the cost of explanatory power is descriptive adequacy. Really powerful explanatory laws of the sort found in theoretical physics do not state the truth.

(How the Laws of Physics Lie, p.2)

I will argue that the accounts [laws of physics} give are generally not true, patently not true by the same practical standards that admit an indefinite number of commonplace phenomenological laws. We have detailed expertise for testing the claim of physics about what happens in concrete situations. When we look to the real implications of our fundamental laws, they do not meet these ordinary standards. Realists are inclined to believe that if theoretical laws are false and inaccurate, then phenomenological laws are more so. I urge just the reverse. When it comes to the test, fundamental laws are far worse off than the phenomenological laws they are supposed to explain.

(How the Laws of Physics Lie, p.3)

She offers three arguments...

(1) The manifest explanatory power of fundamental laws does not argue for their truth.

(2) In fact the way they are used in explanation argues for their falsehood. We explain by ceteris paribus laws, by composition of causes, and by approximations that improve on what the fundamental laws dictate. In all of these cases the fundamental laws patently do not get the facts right.

(3) The appearance of truth comes from a bad model of explanation, a model that ties laws directly to reality. As an alternative to the conventional picture I propose a simulacrum account of explanation. The route from theory to reality is from theory to model, and then from model to phenomenological law. The phenomenological laws are indeed true of the objects in reality—or might be; but the fundamental laws are true only of objects in the model.

(How the Laws of Physics Lie, p.3)

Cartwright's work builds on the claims of Bas van Fraasen that truth has nothing to do with explanatory power.

She writes...

I will argue that the falsehood of fundamental laws is a consequence of their great explanatory power. This is the exact opposite of what is assumed by a well-known and widely discussed argument form—inference to the best explanation. The basic idea of this argument is: if a hypothesis explains a sufficiently wide variety of phenomena well enough, we can infer that the hypothesis is true. Advocates of this argument form may disagree about what counts as well enough, or how much variety is necessary. ( But they all think that explanatory power, far from being at odds with truth, leads us to it. My first line of argument in these essays denies that explanation is a guide to truth...

Numerous traditional philosophical positions bar inferences to best explanations. Scepticism, idealism, and positivism are examples. But the most powerful argument I know is found in Pierre Duhem’s Aim and Structure of Physical Theory, reformulated in a particularly pointed way by Bas van Fraassen in his recent book The Scientific Image. Van Fraassen asks, what has explanatory power to do with ' truth? He offers more a challenge than an argument: show exactly what about the explanatory relationship tends to guarantee that if x explains y and y is true, then x should be true as well. This challenge has an answer in the case of causal explanation, but only in the case of causal explanation...

Causal reasoning provides good grounds for our beliefs in theoretical entities. Given our general knowledge about what kinds of conditions and happenings are possible in the circumstances, we reason backwards from the detailed structure of the effects to exactly what characteristics the causes must have in order to bring them about. I have sometimes summarized my view about explanation this way: no inference to best explanation; only inference to most likely cause. But that is right only if we are very careful about what makes a cause ‘likely’. We must have reason to think that this cause, and no other, is the only practical possibility, and it should take a good deal of critical experience to convince us of this.

We make our best causal inferences in very special situations—situations where our general view of the world makes us insist that a known phenomenon has a cause; where the cause we cite is the kind of thing that could bring about the effect and there is an appropriate process connecting the cause and the effect; and where the likelihood of other causes is ruled out. This is why controlled experiments are so important in finding out about entities and processes which we cannot observe. Seldom outside of the controlled conditions of an experiment are we in a situation where a cause can legitimately be inferred...

Explanatory power is no guarantee of truth, unless van Fraassen’s challenge can be met. I argue that, in the very special case of causal explanation, the challenge is met. In causal explanations truth is essential to explanatory success. But it is only the truth of low-level causal principles and concrete phenomenological laws. Is there no further account that secures the truth of abstract laws as well; no story of 'explanation that shows that abstract laws must be tr.ue if they are to explain?

(How the Laws of Physics Lie, pp.4,10)

In her well known essay Causal Laws and Effective Strategies, Cartwright argued for two kinds of physical laws, laws of nature and causal laws