[2][3] She was educated at University College London and was awarded a first class degree in philosophy in 1932, followed by a PhD in 1934.

Her PhD supervisor was Susan Stebbing[4] who provided MacDonald with financial assistance during her research.

[2] MacDonald joined Girton College, Cambridge, as a Pfeiffer Research Fellow in Moral Sciences between 1934 and 1937.

[2] Along with fellow student Alice Ambrose she secretly (since he did not allow this) made notes during Wittgenstein's lectures, which were later published.

Her view is summarised by Jonathan Wolff as: "statements of natural rights are akin to decisions, declaring 'here I stand', and [she] ... uses an analogy with another area of critical judgement — in her case literary appreciation — to point out the possibility of rational argument through the presentation of reasons".