Haack has said of her career that she is "very independent": rather than follow philosophical fads and fashions, I pursue questions I believe are important, and tackle them in the ways that seem most likely to yield results; I am beholden to no clique or citation cartel; I put no stock in the ranking of philosophy graduate programs over which my colleagues obsess; I accept no research or travel funds from my university; I avoid publishing in journals that insist on taking all the rights to my work; etc., etc.

Naturally, this independence comes at a price; but it also earns me the freedom to do the best work I can, without self-censorship, and to communicate with a much wider audience than the usual "niche literature" does[2]Haack's major contribution to philosophy, in the 1993 book Evidence and Inquiry is her epistemological theory called foundherentism,[3][4][5] which is her attempt to avoid the logical problems of both pure foundationalism (which is susceptible to infinite regress) and pure coherentism (which is susceptible to circularity).

A highly simplified version of this proceeds as follows: Finding an answer using a clue is analogous to a foundational source (grounded in empirical evidence).

Haack published a vigorous essay[8] in the New Criterion, taking strong exception to many of Rorty's views, especially his claim to be a sort of pragmatist.

[9][10] Haack describes her 2003 book Defending Science – Within Reason: Between Scientism and Cynicism, as a defence of scientific inquiry from the moderate viewpoint.

The book offers a sounder and more solid defence of scientific inquiry in response to the narrow logical models of rationality proposed by some philosophers of science.

While stating her disagreement with British philosopher of religion Richard G. Swinburne and Stephen Jay Gould, she referred to the pertinent chapter of her book for a comprehensive understanding of her views on this matter.

Haack believes that while scientists, historians and detectives play a useful role in scientific inquiry, theologians do not.

She points out areas where prior and current religious claims about the natural universe are strongly refuted by the best warranted findings of science.

Haack's work has been reviewed and cited in the popular press, such as The Times Literary Supplement as well as in academic journals.