Philosophy of time seminars increasingly assign physics books alongside traditional philosophical texts, and J. Richard Gott III's "Time Travel in Einstein's Universe" is a natural candidate. The book presents physical possibilities that raise old philosophical questions about causation, free will, and the nature of the past. Students end up writing essays that sit between two disciplines, which makes grading more complicated than usual.

The core challenge is that philosophy and physics reward different habits. A philosophy instructor looks for careful definitions, explicit premises, and conclusions that follow validly, while a physicist wants correct use of established results. A rubric for a cross-disciplinary seminar should name both sets of expectations so that students know they are responsible for each.

It also helps to tell students which discipline governs which kind of claim. A claim about what the equations permit is a physics claim and should be supported accordingly, while a claim about what that implies for free will is a philosophical claim requiring a different kind of argument. Making this distinction explicit prevents essays from blending the two carelessly.

Design a two-part rubric for hybrid essays

A two-part rubric lets instructors score the philosophical argument and the scientific accuracy independently. One half might assess whether premises are stated, whether the logic is valid, and whether objections are considered. The other half might assess whether the physical ideas are described correctly and whether the student avoids overstating what the science has shown.

• States philosophical premises explicitly and checks that the conclusion follows from them.
• Describes physical ideas from the reading accurately and in the student's own words.
• Separates what physics allows from what philosophy concludes.
• Anticipates at least one serious objection and responds to it.
• Uses precise terminology consistently throughout the essay.

Watch for category errors in student arguments

A common mistake in these essays is the category error, where a student treats a mathematical possibility as if it settled a philosophical question. Saying that the equations allow a closed loop in time and therefore free will must be an illusion skips several steps of reasoning. Graders should flag these jumps and ask the student to fill in the missing argument.

The reverse error also occurs, when a student uses an intuition about what feels possible to dismiss a physical result. Both errors can be addressed with the same feedback approach, which is to ask what evidence or argument connects the starting point to the conclusion. Over time, students learn to build those connections explicitly.

Coordinate when two instructors share the grading

Some seminars are co-taught by a philosopher and a physicist, and both grade each essay. In those cases, a calibration session at the start of the term can prevent frustrating disagreements. Reading two or three sample essays together and discussing how each instructor would score them reveals differences in expectations before they affect student grades.

Agreeing on how to combine the two scores is equally important. Averaging them can hide meaningful disagreement, while using the lower score may feel harsh. Whatever method you choose, communicate it to students in advance so that grading feels transparent and fair.

Support instructors with consistent first-pass feedback

Seminar essays are long and conceptually dense, so grading them thoroughly takes a great deal of time. A consistent first pass that identifies the thesis, lists the stated premises, and notes missing objections gives instructors a head start on their analysis. It does not replace their expertise, but it organizes the reading.

AI tools configured with your rubric can produce that kind of structured overview for each essay. Instructors then spend their time evaluating the quality of the argument rather than searching for its parts. That shift makes it easier to give the detailed written feedback seminar students expect.