The philosophy of science is as useful to scientists as ornithology is to birds.

The line is used as a dismissive analogy suggesting that reflective, second-order analysis of science (philosophy of science) has little practical value for working scientists, much as a scholarly study of birds would not be useful to birds themselves. The earliest close match located in the provided material is Steven Weinberg quoting it in a 1987 speech, explicitly saying he could not remember the source.

It frames philosophy of science as an external commentary that does not directly aid day-to-day scientific practice, implying that scientists can do their work without engaging with philosophical analysis. Later writers sometimes add the caveat that such “external” study can still indirectly benefit its subject (e.g., conservation outcomes from ornithology).

I’ve heard the remark (although I forget the source) that the philosophy of science is just about as useful to scientists as ornithology is to birds.

the philosophy of science is about as useful to scientists as ornithology is to birds

‘the philosophy of science is about as useful to scientists as ornithology is to birds’ (with a note that ornithologists can help birds survive)